Update autobahntestsuite to 0.5.2

Also small mostly insignificant changes to tests.
Remove support for Websocket hixie76 draft

It was only used by Safari 5.0.1 and possibly 5.1. Their market share
is dropping as we speak. It was also insecure (disabled in Firefox
for that reason).

This will allow us to make much more efficient and cleaner code for
the rest of the Websocket versions we support (drafts 7 to 17 + RFC),
which are pretty much all versions seen in the wild excluding the
one we're removing here.
Fix getting started example, missing env
All frames sent from client to server MUST be masked

Good in theory, but implementations may vary. If something stops
working after this commit we might need some tweaks to support
existing clients.

Please try it and give feedback.