Comment 3 for bug 194251

My "~jamesh/bzr-dbus/kill-broadcast-daemon" branch completes these changes, doing the following:
 1. moves the URL mapping code to LanGateway
 2. makes Activity.advertise_branch() and Activity.announce_revision_urls() send a DBus signal directly.
 3. makes LanGateway listen for Revision signals from any source.
 4. removes the Broadcast class and associated code.

This maintains compatibility with the UDP broadcast protocol, but changes the DBus protocol seen locally (so computers with the new and old bzr-dbus installed can talk to each other). It also means that the URL mapping is only done when transmitting revisions over the network: local branches will be announced with unmapped URLs.