README: Small tweaks/clarifications/plain text beautifications (ldc-developers#2553)

Removed the d1/ltsmaster branch links, as they are not very useful
(what would a user do on the GitHub page?) and bloat the file when
viewed in a terminal/editor.

Author: dnadlinger

README.md

@@ -1,27 +1,27 @@
 LDC – the LLVM-based D Compiler
 ===============================
 
-[![Build Status](https://circleci.com/gh/ldc-developers/ldc/tree/master.svg?style=svg)][6]
-[![Build Status](https://semaphoreci.com/api/v1/ldc-developers/ldc/branches/master/shields_badge.svg)][4]
-[![Build Status](https://travis-ci.org/ldc-developers/ldc.png?branch=master)][1]
-[![Build Status](https://ci.appveyor.com/api/projects/status/2cfhvg79782n4nth/branch/master?svg=true)][5]
-[![Bountysource](https://www.bountysource.com/badge/tracker?tracker_id=283332)][3]
+[![Build Status](https://circleci.com/gh/ldc-developers/ldc/tree/master.svg?style=svg)][1]
+[![Build Status](https://semaphoreci.com/api/v1/ldc-developers/ldc/branches/master/shields_badge.svg)][2]
+[![Build Status](https://travis-ci.org/ldc-developers/ldc.png?branch=master)][3]
+[![Build Status](https://ci.appveyor.com/api/projects/status/2cfhvg79782n4nth/branch/master?svg=true)][4]
+[![Bountysource](https://www.bountysource.com/badge/tracker?tracker_id=283332)][5]
 
-The LDC project aims to provide a portable D programming language
-compiler with modern optimization and code generation capabilities.
+The LDC project provides a portable D programming language compiler
+with modern optimization and code generation capabilities.
 
-The compiler uses the official DMD frontends to support the latest
+The compiler uses the official DMD frontend to support the latest
 version of D2, and relies on the LLVM Core libraries for code
 generation.
 
 LDC is fully Open Source; the parts of the code not taken/adapted from
 other projects are BSD-licensed (see the LICENSE file for details).
 
 Please consult the D wiki for further information:
-http://wiki.dlang.org/LDC
+https://wiki.dlang.org/LDC
 
-D1 is no longer available; see the [d1](https://github.com/ldc-developers/ldc/tree/d1)
-Git branch for the last version supporting it.
+D1 is no longer available; see the `d1` Git branch for the last
+version supporting it.
 
 
 Installation
@@ -34,89 +34,83 @@ Installation
 For several platforms, there are stand-alone binary builds available at the
 [GitHub release page](https://github.com/ldc-developers/ldc/releases).
 
-For bleeding-edge users, we also provide the
-[latest successful Continuous Integration builds](https://github.com/ldc-developers/ldc/releases/tag/CI)
-with enabled LLVM & LDC assertions.
+For bleeding-edge users, we also provide the [latest successful
+Continuous Integration builds](https://github.com/ldc-developers/ldc/releases/tag/CI)
+with enabled LLVM & LDC assertions (significantly increasing compile times).
 
-The [official D version manager (a.k.a. install script)](https://dlang.org/install.html) can also
-be used to install LDC.
+The [dlang.org install script](https://dlang.org/install.html)
+can also be used to install LDC:
 
-```
-# Download the install script to '~/dlang/install.sh'
-mkdir -p ~/dlang && wget https://dlang.org/install.sh -O ~/dlang/install.sh && chmod 755 ~/dlang/install.sh
+    curl -fsS https://dlang.org/install.sh | bash -s ldc
 
-# Download & extract the latest stable LDC
-~/dlang/install.sh install ldc
-```
+In addition, LDC is available from various package managers:
 
-In addition, some package managers include recent (but not necessarily the 
-latest) versions of LDC, so manually installing it might not be necessary. 
+|              | Command                                     |
+| ------------ | ------------------------------------------- |
+| Arch Linux   | `pacman -S ldc`                             |
+| Debian       | `apt install ldc`                           |
+| Fedora       | `dnf install ldc`                           |
+| Gentoo       | `layman -a ldc`                             |
+| Homebrew     | `brew install ldc`                          |
+| Ubuntu       | `apt install ldc`                           |
+| Snap         | `snap install --classic --channel=edge ldc` |
 
-|              | Command               |
-| ------------ | --------------------- |
-| Arch Linux   | `pacman -S ldc`       |
-| Debian       | `apt install ldc` |
-| Fedora       | `dnf install ldc`     |
-| Gentoo       | `layman -a ldc`       |
-| Homebrew     | `brew install ldc`    |
-| Ubuntu       | `apt install ldc` |
-
-Further, LDC can be installed as snap package (possibly outdated):
-
-    $ sudo snap install --classic --channel=edge ldc
+Note that these packages **might be outdated** as they are not
+currently integrated into the project release process.
 
 
 #### Windows
 
 The latest official releases can be downloaded from the
 [GitHub release page](https://github.com/ldc-developers/ldc/releases).
 
-For bleeding-edge users, we also provide the
-[latest successful Continuous Integration builds](https://github.com/ldc-developers/ldc/releases/tag/CI)
-with enabled LLVM & LDC assertions.
+For bleeding-edge users, we also provide the [latest successful
+Continuous Integration builds](https://github.com/ldc-developers/ldc/releases/tag/CI)
+with enabled LLVM & LDC assertions (significantly increasing compile times).
 
-LDC for Windows relies on the Microsoft linker. So you'll either need
+LDC for Windows relies on the Microsoft linker and runtime libraries,
+which can be obtained by either installing
 [Visual Studio](https://www.visualstudio.com/downloads/) 2015 or 2017
 with Visual C++, or the stand-alone
 [Visual C++ Build Tools](http://landinghub.visualstudio.com/visual-cpp-build-tools).
 
+
 ### Building from source
 
 In-depth material on building and installing LDC and the standard
 libraries is available on the project wiki for
-[Linux and OS X](http://wiki.dlang.org/Building_LDC_from_source) and
+[Linux and macOS](http://wiki.dlang.org/Building_LDC_from_source) and
 [Windows](http://wiki.dlang.org/Building_and_hacking_LDC_on_Windows_using_MSVC).
 
-If you have a working C++ build environment, CMake, and a current LLVM (≥ 3.7)
-available, there should be no big surprises.
-Building LDC also requires a working D compiler, DMD and LDC are supported.
-(LDC 0.17 is the last version that does not need a D compiler,
-and for that reason we try to maintain it in the
-[ltsmaster](https://github.com/ldc-developers/ldc/tree/ltsmaster) branch).
-
-Do not forget to make sure all the submodules (druntime, phobos, dmd-testsuite)
+If you have a working C++/D build environment, CMake, and a current LLVM
+version (≥ 3.7) available, there should be no big surprises. Do not
+forget to make sure all the submodules (druntime, phobos, dmd-testsuite)
 are up to date:
 
     $ cd ldc
     $ git submodule update --init
 
+(DMD and LDC are supported as host compilers. For bootstrapping
+purposes, LDC 0.17, the last version not to require a D compiler, is
+maintained in the `ltsmaster` branch).
+
+
 Contact
 -------
 
 The best way to get in touch with the developers is either via the
-digitalmars.D.ldc forum/newsgroup/mailing list
-(http://forum.dlang.org) or our [Gitter chat](http://gitter.im/ldc-developers/main).
+[digitalmars.D.ldc forum/newsgroup/mailing list](https://forum.dlang.org)
+or our [Gitter chat](http://gitter.im/ldc-developers/main).
 There is also the #ldc IRC channel on FreeNode.
 
 For further documentation, contributor information, etc. please see
-the D wiki: http://wiki.dlang.org/LDC
+[the D wiki](https://wiki.dlang.org/LDC).
 
 Feedback of any kind is very much appreciated!
 
 
-[1]: https://travis-ci.org/ldc-developers/ldc "Travis CI Build Status"
-[2]: https://coveralls.io/r/ldc-developers/ldc "Test Coverage"
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+[1]: https://circleci.com/gh/ldc-developers/ldc/tree/master "Circle CI Build Status"
+[2]: https://semaphoreci.com/ldc-developers/ldc "Semaphore CI Build Status"
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+[4]: https://www.bountysource.com/teams/ldc-developers/issues "Bountysource"
 [5]: https://ci.appveyor.com/project/kinke/ldc/history "AppVeyor CI Build Status"
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