Bump version to 2.0.23

CHANGES.rst

@@ -7,7 +7,7 @@ This is a record of changes made between each Mutalyzer release.
 Version 2.0.23
 ---------------
 
-Release date to be decided.
+Released on November 9th 2016.
 
 - Fix for internal server error in the position converter triggered by
   non-variant description (`#333

mutalyzer/__init__.py

@@ -21,8 +21,8 @@ from __future__ import unicode_literals
 # [1] http://peak.telecommunity.com/DevCenter/setuptools#specifying-your-project-s-version
 # [2] http://semver.org/
 
-__version_info__ = ('2', '0', '23', 'dev')
-__date__ = '20 Sep 2016'
+__version_info__ = ('2', '0', '23')
+__date__ = '9 Nov 2016'
 
 
 __version__ = '.'.join(__version_info__)