[Twisted-Python] PyPy buildbot, less failed tests

[Craig Rodrigues]

I would like to acknowledge the contributions of Ville SkyttÀ who submitted
several patches to close open file descriptors in various Twisted tests.

I looked at these two PyPy builds:

https://buildbot.twistedmatrix.com/builders/ubuntu16.04-pypy5/builds/207
52 Failed tests (20 failures, 32 errors)

https://buildbot.twistedmatrix.com/builders/ubuntu16.04-pypy5/builds/208
32 Failed tests (15 failures, 17 errors)

This reduction is directly due to Ville's contributions.
Thank you Ville!!

--
Craig