Updated readme

Author: ale5000-git

README.md

@@ -1,4 +1,7 @@
 # PyCompatLayer - compatibility layer for Python
+[![Supported Python versions](https://img.shields.io/pypi/pyversions/PyCompatLayer.svg)](https://pypi.python.org/pypi/PyCompatLayer/)
+
 It make all versions of Python behaving as the latest version of Python 3.x.  
-This will allow you to be compatible with all versions of Python without effort.  
+This will allow you to be compatible with all versions of Python without effort.
+
 It is still under development, not all functions are supported.