Set version number to 4.0b2
Fix binary websocket connections
Merge pull request #1091 from xose/patch-1

Fix binary websocket connections
Merge branch 'master' of github.com:tornadoweb/tornado
Add tests for both binary and unicode messages in websockets.
Disable twisted tests on pypy on travis-ci since they seem to be flaky.

They were already disabled in tox.ini.