Experiment with bridge: true property

[cblgh]

posting @noffle's idea from irc here

00:17:53 < noffle> fyi that a cabal<->irc mirror exists: https://github.com/cabal-club/cabal-irc
00:20:58 < noffle> it'd be cool if cabal chat messages had an optional property that said "hey this is a msg from a bridge" so clinets could render those messages in a more aesthetically pleasing +
                   readable way
00:21:03 < noffle> very easy to add

[garbados]

What if also bridge: { source: "{app_name}"}, similar to how an app authenticating with Oauth must name itself? This allows a client to give a user this experience:

00:21:03 [cabal-irc] < noffle> very easy to add