Version 0.2.1

This is basically applying a version number to the changes already made.

I am following the logic A.B.C where A is for complete changes to the
plugin code or to the way it works; B is for increased functionality
(i.e. the plugin does new things); and C for all other changes which do
not add functionality.

I’m merging readme.txt into readme.md to avoid duplication in
documentation.
0.2.2 Fix: Aborts if WP version unsupported, etc.

* Fixed: Aborts if WordPress version is unsupported
* Minimum WordPress version changed to 3.3.0, according to
[Plugin-Datei Doktor](http://de.wpseek.com/pluginfilecheck/)
* Added `LICENSE.txt` and `LICENSE.md` from [TheFox /
GPLv3.md](https://github.com/TheFox/GPLv3.md)
Typos
Merge pull request #7 from Tintazul/master

Version 0.2.2