Revert "Remove the Twisted adapter to get 0.9.6 out the door"

The Twisted adapter needs a few cosmetic changes, but otherwise works
fine. This reverts commit 982707dc1a2efd2544125d74a218d3f03390d521.
Fix the Twisted adapter to correctly function with current HEAD.
Merge pull request #259 from wulczer/bring-back-twisted-adapter-203

Bring back the Twisted adapter