feat(device-selection): new icon for audio output

ref(toolbar): remove use-new-toolbox class

This commit adds a state getter that considers checking the enabled/disabled state of the calendar feature, so then other features don’t have to do it manually.

Very likely I broke something subtle and I'm prepared to fix it.

WebRTC plugin support has been axed, this is now dead code.

Syntax changed slightly with an update to CocoaPods.

[RN] Reload screen a catch all

Adds a fatal error state on which will depend whether or not the reload
screen is to be displayed. It is to happen when a relevant fatal error
action is not claimed by any feature for error recovery (the recoverable
flag is not set).

This reverts commit 9e0fee6c7d.

WebRTC requires Java 8, and Java 7 is now considered unsupported:
https://groups.google.com/forum/?utm_medium=email&utm_source=footer#!msg/discuss-webrtc/V1h2uQMDCkA/RA-uzncVAAAJ

- Instead of having 4 listeners for local connection status
  updates and 1 for remote, remove two of the redundant listeners.
- Instead of calling into 4 separate VideoLayout methods to update a
  participant's connection status, expose one handler.

When in audio only, the video should not be shown and instead the
avatar should display.

Mobile looping sounds

Up until now, mobile was oblivious to participants' presence state. Presence
state handling is required (probably, amongst other things) for "call flows".
So, let's add it! This is done by gathering the presence state when a
participant first joins, and handling subsequent changes.

Fix the "mute ping pong" for once and for all. This patch takes a new approach
to the problem: it keeps track of the user generated CallKit transaction ations
and avoids calling the delegate method in those cases.

This results in a much cleaner and easier to understand handling of the flow: if
the delegate method is called it means the user tapped on the mute button. When
we sync the muted state in JS with CallKit the delegate method won't be called
at all, thus avoiding the ping-pong altogether.

In addition, make sure all CallKit methods run in the UI thread. CallKit will
call our delegate methods in the UI thread too, thsu there is no need to
synchronize access to the listener / pending action sets.

Not all TRACK_ actions include the `local` attribute, so use the underlying
`jitsiTrack` to check it.

* ref(video-layout): move middleware for TRACK_ADDED

* ref(video-layout): call mucJoined when redux knowns of conference join

old values: 0-39% -> red, 40-69% -> yellow, 70%+ -> green
new values: 0-9% -> red, 10-29% -> yellow, 30%+ -> green