Adds base/sounds feature which allows other features to register a sound
source under specified id. A new SoundsCollection component will then
render corresponding HTMLAudioElement for each such sound. Once "setRef"
callback is called by the HTMLAudioElement, this element will be added
to the Redux store. When that happens sound can be played through the
new 'playSound' action which will call play() method on the stored
HTMLAudioElement instance.

The animation for toggling filmstrip visibility was lagging on
Safari. Even though the background video is set to hidden, it is
still causing issues. Setting the background to display none
instead does help but might interfere with animations. So instead
do the easy thing and re-use logic used for Firefox to not show
the background video.

Pre-existing logic made it so numbers were assumed as valid
if no validation url was specified. To be consistent with
the validation server, the faked number should include a
+ at the beginning.

* feat(invite): be able to call numbers from the invite dialog

The major changes:
- Remove DialOutDialog, its views, redux hooks, css, and images.
  Its main functionality has been moved into AddPeopleDialog.
- Modify the AppPeopleDialog styling a bit so it is wider.
- Add phone numbers to AddPeopleDialog search results. Phone
  numbers are validated in parallel with the request for people
  and then appended to the result. The validation includes
  an ajax to validate the number is recognized as dialable by
  the server. The trigger for the validation is essentially if
  the entered input is numbers only.
- AddPeopleDialog holds onto the full object representation of
  an item selected in MultiSelectAutocomplete. This is so
  selected items can be removed on successful invite, leaving
  only unsuccessful items.
- More granular error handling on invite so individual invitees
  can be removed from the selected items list.

* squash: change load state, new regex for numbers

* squash: change strings, auto prepend 1 if no country code, add reminders

In 94813bc0fd (diff-6e9552c9bd8e61c8f277c21220160234)
two local variables got removed (AUTH_KEY_FILE and AUTH_CRT_FILE), which are used by the sed command
below to configure the virtualhost for auth.

For the static page an error message displays stating no room
was specified. On mobile for unsupported browsers, the dial in
info will not show.

The new libwebrtc.jar contains an extra unused class file, when proguard is enabled result in the following warning:

org.chromium.build.BuildHooksAndroidImpl: can't find superclass or interface org.chromium.build.BuildHooksAndroid

java.lang.RuntimeException: Tried to access a JS module before the React instance was fully set up. Calls to ReactContext#getJSModule should only happen once initialize() has been called on your native module.
	at com.facebook.react.bridge.ReactContext.getJSModule(ReactContext.java:102)
	at com.rnimmersive.RNImmersiveModule.emitImmersiveStateChangeEvent(RNImmersiveModule.java:74)
	at org.jitsi.meet.sdk.JitsiMeetView.onWindowFocusChanged(JitsiMeetView.java:504)
	at android.view.View.dispatchWindowFocusChanged(View.java:10257)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1193)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewGroup.dispatchWindowFocusChanged(ViewGroup.java:1197)
	at android.view.ViewRootImpl$ViewRootHandler.handleMessage(ViewRootImpl.java:3602)
	at android.os.Handler.dispatchMessage(Handler.java:102)
	at android.os.Looper.loop(Looper.java:154)
	at android.app.ActivityThread.main(ActivityThread.java:6119)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

Updates lib-jitsi-meet to d4b78721.

Implements the promised based getStats. Enables them for Safari and FF.

Updates react-native-webrtc to get rid of Java 8 requirement for
the Android app.

Solves a GitHub warning in lib-jitsi-meet about a vulnerability in a
uglifyjs-webpack-plugin dependency.

WebRTC used to report createAnswer (and createOffer) NSError with key
"error". But now the key's called "NSLocalizedDescription".

Additionally, NSMutableDictionary doesn't accept nil.

doc: Add clarifying text to the top of the readme.

* feat: Whitelists the gatherStats option.

* doc: Replaces obsolete disableStats option with gatherStats.

* deps: update jquery version

* squash: resize thumbnails after appending shared thumb

This forces jquery animate to show the thumbnail somehow...
Remote thumbnails basically work this way (append to filmstrip
and then resize filmstrip thumbnails) so I just copied that
implementation. ... So I admit I lost this fight because
even after looking at jquery I couldn't understand why
it doesn't work on the first resize but does on the second.
Plus I'm being put on a strict timebox to update jquery.

* squash: getJSON no longer supports .success

Looks like this guy snuck into the commit.

The difference from this change and 88325ae is there is no
attempt to do this in redux. This is the safer change in that
the cleanup logic is known only to trigger on hangup.

This reverts commit 88325aeef2.
Turns out a conference with a password triggers a failed conference
join. It's going to be tricky to decipher when to do actual
cleanup, and where to shove that code, so reverting is easier for
now.

This gets around the issue of a cdn page being opened.

Recent changes in lib-jitsi-meet probably led to (1) our
RTCPeerConnection customizations on react-native not being used which is
a problem because we need them for at least NAT64 on iOS in order to
pass the review in Apple's App Store and (2) unexpected exceptions
inside react-native-webrtc.

The Promise-based WebRTC API should be merged from react-native-webrtc's
upstream but I don't want to do it right now because last time we got
multiple bugs in addition.

Destroy local tracks and also destroy large video so the
user does not wonder why camera (and mic) are still enabled
even though hangup has been pressed.

config: Whitelists the desktopSharingFrameRate config key.