update(docs): Update README for serving docs site

Fix issue raised in forums: https://groups.google.com/forum/#!topic/ngmaterial/XWqE2nLPS3E

  Closes angular#6436

docs/README.md

@@ -1,35 +1,13 @@
 Documentation
 -------------
 
-The Angular Material **Live Docs** are generated from the source code and demos; and, in fact, the
-Live Docs actually use the Angular Material components and themes.
+The Angular Material **Live Docs** are generated from the source code. In fact, the Angular Material documentation itself uses the Angular Material layout, components and themes.
 
 > Our build process uses **[dgeni](https://github.com/angular/dgeni)**, the wonderful documentation
 generator built by [Pete Bacon Darwin](https://github.com/petebacondarwin).
 
 To view the Live Docs (locally):
 
 1. Install the dependencies using `npm install`
-2. Install the dependencies using `bower install`
-3. Build the docs using `gulp docs`
-4. Run `gulp watch` to auto-rebuild docs (optional)
-5. Start an HTTP Server; the example below uses port 8080
-6. Open browser at `http://localhost:8080`
-
-```bash
-# Build & deploy docs to `dist/docs`
-gulp docs
-
-# Watch source dirs for changes and rebuild
-gulp watch
-
-# Use the built-in gulp server with live reload
-gulp server
-
-# Alternatively, install httpster globally; if not already installed
-npm install -g httpster
-
-# And then launch the webserver
-# NOTE: unlike `gulp server` this will not auto-reload the HTML
-httpster -p 8080 -d ./dist/docs
-```
+1. Build the docs and serve with 'live reload' using `npm run watch`
+1. Open Browser for [http://localhost:8080](http://localhost:8080)

src/core/services/layout/layout.attributes.scss

@@ -210,7 +210,7 @@ $layout-breakpoint-lg:     1920px !default;
   [#{$name}],
   [#{$name}="start stretch"] // defaults
   {
-    justify-content : start;
+    justify-content :flex-start;
     align-content : stretch;
     align-items: stretch;
   }