README.md: add supported python versions badge

Cosimo Lupo · Cosimo Lupo · commit de02d36cab3b · 2016-10-18T13:07:06.000+01:00
This is just a dummy commit in order to make the CI actually run.
Previously, I tagged the preceding commit but I specified "[skip ci]", and so the auto-deployment did not trigger... Sorry!
diff --git a/README.md b/README.md
@@ -1,4 +1,5 @@
 [![PyPI](https://img.shields.io/pypi/v/booleanOperations.svg)](https://pypi.org/project/booleanOperations/)
+![Python Versions](https://img.shields.io/badge/python-2.7%2C%203.4%2C%203.5-blue.svg)
 
 BooleanOperations
 =================

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,5 @@`
`1`	`1`	`[![PyPI](https://img.shields.io/pypi/v/booleanOperations.svg)](https://pypi.org/project/booleanOperations/)`
	`2`	`+![Python Versions](https://img.shields.io/badge/python-2.7%2C%203.4%2C%203.5-blue.svg)`
`2`	`3`
`3`	`4`	`BooleanOperations`
`4`	`5`	`=================`