Add changelog entries for the soon-to-be-released 3.2.2 and 3.1.5 patch releases

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2623 ed100bfc-0583-0410-97f2-c26b58777a21
Released 3.1.5


Conflicts:

	CHANGES.txt
	docs/source/conf.py
	setup.cfg

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2624 ed100bfc-0583-0410-97f2-c26b58777a21
Released 3.2.2

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2627 ed100bfc-0583-0410-97f2-c26b58777a21