* fix(conference) Fix different bugs with startMuted policy.
If the user changes mute state after joining the call and before the other participats join the call, make sure those state changes are honored.

* feat(startMuted) Ignore startMuted in Jingle from focus.
Apply startMuted policy based on startMuted setting in room meta data.
Moderator settings and AV moderation settings will now be propagated to new endpoints joining the call through room meta data.
Advertise a new capability 'start-muted-room-metadata' to Jicofo for feature detection.