[enh] release 0.5.1

CHANGELOG

 Changelog
 =========
-0.5.1 (unreleased)
+0.5.1 (2015-03-11)
 ------------------
 - fix whitespace duplication when using .insert()

setup.py

@@ -12,7 +12,7 @@ except ImportError:
 setup(name='redbaron',
-      version='0.5',
+      version='0.5.1',
       description='Abstraction on top of baron, a FST for python to make writing refactoring code a realistic task',
       author='Laurent Peuch',
       long_description=read_md("README.md") + "\n\n" + open("CHANGELOG", "r").read(),