Release 17.1.0

Tag 16.6.0 release

Tag 16.5.0 release

Tag 16.4.1 release

Tag 16.4.0 release

Tag 16.3.2 release

Tag 16.3.1 release

Tag 16.3.0 release

Tag 16.2.0 release

Tag 16.1.1 release.

git-svn-id: svn://svn.twistedmatrix.com/svn/Twisted/tags/releases/twisted-16.1.1@47205 bbbe8e31-12d6-0310-92fd-ac37d47ddeeb