matteocampana-zz

Configure colibri channels according to rtpLevelRelayType property

1

When colibri channels are created, use the rtpLevelRelayType config property to configure rtp-level-relay-type channel element. (PR recreated after rebase).

Implement -rtpLevelRelayType command line parameter to specify which type of rtp relay should be used with the created conferences: translator (default) or mixer. NOTE: it requires https://github.com/jitsi/jitsi/pull/261 and https://github.com/jitsi/jicofo/pull/86.