ipv6 support

[mtmcgrew]

Does not work with v6 addresses

File "/usr/lib/python2.6/site-packages/stompest-2.1.6-py2.6.egg/stompest/protocol/failover.py", line 189, in _parse
raise ValueError('invalid uri: %s [%s]' % (self.uri, msg))
exceptions.ValueError: invalid uri: tcp://xxx:xxx:c081:20::70:65001 [invalid broker(s): 'NoneType' object has no attribute 'groupdict']

[nikipore]

Are you or someone from your team willing to dig into that? Should be straightforward for sync; not so sure about async because I don't know whether/how transparently Twisted supports that.