BugFix - In context of twisted, when running unit tests, will get an error -

   Failure: twisted.trial.util.DirtyReactorAggregateError: Reactor was unclean.
   <DelayedCall 0x27b6b00 [0.934782028198s] called=0 cancelled=0 LinusWebSocketClientProtocol.onOpenHandshakeTimeout()>
This happens because onOpenHandshakeTimeout has a default of 5 seocnds, and the timer is not canceled even if
we open the websocket. Thne if your test completes within 5 seconds you'll get this error.

This Patch adds succeedHandshake() to WebSocketClientProtocol which then cancels the openHandshakeTimeoutCall.