Conflicts:
	JitsiConference.js
	modules/statistics/CallStats.js

Fixes name of the DOMINANT_SPEAKER_CHANGED event.

fix: Fixes a jshint or eslint warning.

Cleans the statistics code a bit

hack: Assumes a lower packet loss rate when video is muted.

fix: Use only packet loss for the send direction.

This is only temporary, since we suspect that the calculation for the
receive direction is incorrect.

Conn quality

Second attempt on #292

Fix Uncaught TypeError: Cannot read property 'getTracks' of undefined

If there was no notification from the JVB about the connectivity status
it means it's connected. That's because the bridge does not send any
notification unless there is a problem.

The manager will not forward the event if the participant does not
exist, as it is not expected to get the event for "undefined"
participant.

Initialize lock state on room join.

Cleans up code. Paces the increase of connection quality. Take ramp-up
into account. Uses sending bitrate by default whenever possible (with
and without simulcast, as long as we know the sending bitrate and
resolution).

Updates the packet loss based calculation (used whenever we don't know
the sending bitrate and input resolution) with hard-coded thresholds,
so that it doesn't scale linearly (15% packet loss doesn't yield 85%
connection quality).