[Twisted-web] Twisted + OpenSSL 1.0.2f issues resolved

Hi everyone, Since Tristan Seligmann has fixed https://twistedmatrix.com/trac/ticket/8189 , and the CFFI crash-on-shutdown bugs have been resolved upstream, Twisted is now fully compatible with OpenSSL 1.0.2f as included in Cryptography 1.2.2, and as included in distributions that have been updated. This fix is in Twisted trunk, but did not make it into Twisted 16.0. Twisted 16.1 will include the fix. Thanks to Tristan and Glyph (the reviewer) for getting this issue fixed. - Amber