Remove Travis CI configuration and badge (#3, thanks @striezel)

The tests are not running on Travis CI anymore, so there is no
point in keeping that stuff around.

[skip ci]

README.md

@@ -2,7 +2,7 @@
 
 atomic lite - a C++11 atomic operations library for C++98 and later
 
-[![Language](https://img.shields.io/badge/C%2B%2B-98/11/14/17-blue.svg)](https://en.wikipedia.org/wiki/C%2B%2B#Standardization) [![License](https://img.shields.io/badge/license-BSL-blue.svg)](https://opensource.org/licenses/BSL-1.0) [![Build Status](https://github.com/martinmoene/atomic-lite/actions/workflows/ci.yml/badge.svg)](https://github.com/martinmoene/atomic-lite/actions/workflows/ci.yml) [![Build Status](https://travis-ci.org/martinmoene/atomic-lite.svg?branch=master)](https://travis-ci.org/martinmoene/atomic-lite) [![Build status](https://ci.appveyor.com/api/projects/status/gpmw4gt271itoy2n?svg=true)](https://ci.appveyor.com/project/martinmoene/atomic-lite) [![Version](https://badge.fury.io/gh/martinmoene%2Fany-lite.svg)](https://github.com/martinmoene/atomic-lite/releases) [![download](https://img.shields.io/badge/latest-download-blue.svg)](https://raw.githubusercontent.com/martinmoene/atomic-lite/master/include/nonstd/atomic.hpp) [![Conan](https://img.shields.io/badge/on-conan-blue.svg)](https://bintray.com/martinmoene/nonstd-lite/atomic-lite%3Anonstd-lite/_latestVersion) [![Try it online](https://img.shields.io/badge/on-wandbox-blue.svg)](https://wandbox.org/permlink/GzoTkzwF7t5ncDg0) [![Try it on godbolt online](https://img.shields.io/badge/on-godbolt-blue.svg)](https://godbolt.org/z/vMueSf)
+[![Language](https://img.shields.io/badge/C%2B%2B-98/11/14/17-blue.svg)](https://en.wikipedia.org/wiki/C%2B%2B#Standardization) [![License](https://img.shields.io/badge/license-BSL-blue.svg)](https://opensource.org/licenses/BSL-1.0) [![Build Status](https://github.com/martinmoene/atomic-lite/actions/workflows/ci.yml/badge.svg)](https://github.com/martinmoene/atomic-lite/actions/workflows/ci.yml) [![Build status](https://ci.appveyor.com/api/projects/status/gpmw4gt271itoy2n?svg=true)](https://ci.appveyor.com/project/martinmoene/atomic-lite) [![Version](https://badge.fury.io/gh/martinmoene%2Fany-lite.svg)](https://github.com/martinmoene/atomic-lite/releases) [![download](https://img.shields.io/badge/latest-download-blue.svg)](https://raw.githubusercontent.com/martinmoene/atomic-lite/master/include/nonstd/atomic.hpp) [![Conan](https://img.shields.io/badge/on-conan-blue.svg)](https://bintray.com/martinmoene/nonstd-lite/atomic-lite%3Anonstd-lite/_latestVersion) [![Try it online](https://img.shields.io/badge/on-wandbox-blue.svg)](https://wandbox.org/permlink/GzoTkzwF7t5ncDg0) [![Try it on godbolt online](https://img.shields.io/badge/on-godbolt-blue.svg)](https://godbolt.org/z/vMueSf)
 
 A Work in progress. Suggested by Peter Featherstone.