Subject: Bridging
Master-Only: true

The bridging core no longer uses the stasis cache for bridge
snapshots.  The latest bridge snapshot is now stored on the
ast_bridge structure itself.

The following APIs are no longer available since the stasis cache
is no longer used:
  ast_bridge_topic_cached()
  ast_bridge_topic_all_cached()

A topic pool is now used for individual bridge topics.

The ast_bridge_cache() function was removed since there's no
longer a separate container of snapshots.

A new function "ast_bridges()" was created to retrieve the
container of all bridges.  Users formerly calling
ast_bridge_cache() can use the new function to iterate over
bridges and retrieve the latest snapshot directly from the
bridge.

The ast_bridge_snapshot_get_latest() function was renamed to
ast_bridge_get_snapshot_by_uniqueid().

A new function "ast_bridge_get_snapshot()" was created to retrieve
the bridge snapshot directly from the bridge structure.

The ast_bridge_topic_all() function now returns a normal topic
not a cached one so you can't use stasis cache functions on it
either.

The ast_bridge_snapshot_type() stasis message now has the
ast_bridge_snapshot_update structure as it's data.  It contains
the last snapshot and the new one.
