Add changelog, prepare initial release

Author: d-frey

README.md

@@ -20,6 +20,7 @@ The Art of C++ / Operators is a zero-dependency C++11 single-header library that
 [Commutativity](#commutativity)<br/>
 [RValue References](#rvalue-references)<br/>
 [noexcept](#noexcept)<br/>
+[Changelog](#changelog)<br/>
 [License](#license)
 
 ## Preface
@@ -895,6 +896,14 @@ work-around:
 
 With this little hack, The Art of C++ / Operators can be used with GCC 4.4+.
 
+## Changelog
+
+### 1.0.0
+
+Released 2018-02-13
+
+* Initial release.
+
 ## License
 
 The Art of C++ is certified [Open Source](http://www.opensource.org/docs/definition.html) software. It may be used for any purpose, including commercial purposes, at absolutely no cost. It is distributed under the terms of the [MIT license](http://www.opensource.org/licenses/mit-license.html) reproduced here.