Bump version to 2.0.21

CHANGES.rst

@@ -7,7 +7,7 @@ This is a record of changes made between each Mutalyzer release.
 Version 2.0.21
 --------------
 
-Release date to be decided.
+Released on June 24th 2016.
 
 - Fix typo in batch SNP converter, causing all batch jobs to stall (`#409
   <https://github.com/mutalyzer/mutalyzer/pull/409>`_).

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', '21', 'dev')
-__date__ = '22 Jun 2016'
+__version_info__ = ('2', '0', '21')
+__date__ = '24 Jun 2016'
 
 
 __version__ = '.'.join(__version_info__)