* Prints errors in case of wrong initialization.

Not printing can masks some errors in the code.

* Allow only one Follow Me moderator in a meeting.

* Sends Follow Me state with all presences of the moderator.

This fixes an issue where the moderator sends the Follow Me state and then for example mute or unmute video (this will produce a presence without Follow Me state) and the new comers will not reflect current Follow Me state till a change of it comes.

* Changes fixing comments.

* Changes fixing comments.

- handle some weird bug
(https://github.com/firebase/firebase-ios-sdk/issues/233)
- use a common function to extract the URL off a dynamic link

Replace the Swift array with an Objective-C one, since it's going to store
Objective-C objects and not Swift objects (or Swift objects which inherit from
NSObject, which is equivalent).

This avoids the need for JMCallKitEventListenerWrapper entirely, since an
NSArray can store NSObjectProtocol objects, unlike a Swift array, which prompted
the creation of the wrapper in the first place.

Dear reader, I'm not proud at all of what you are about to read, but sometimes
life just gives you lemons, so enjoy some lemonade!

Joining a conference implies first creating the XMPP connection and then joining
the MUC. It's very possible the XMPP connection was made but there was no chance
for the conference to be created.

This patch fixes this case by artificially genrating a conference terminated
event in such case. In order to have all the necessary knowledge for this event
to be sent the connection now keeps track of the conference that runs it.

In addition, there is an even more obscure corner case: it's not impossible to
try to disconnect when there is not even a connection. This was fixed by
creating a fake disconnect event. Alas the location URL is lost at this point,
but it's better than nothing I guess.

This legacy code was added about a year ago to ease the migration between
releases:
631f51d627

I consider this not to be needed anymore.

The SDK will now search for an asset called "CallKitIcon" on the main bundle,
and fallback to a built-in asset it it's not there, allowing SDK users to
customize it by just adding asset with that name.

Removes Edge support.

When CallKit is enabled / disabled, a new CXProvider must be created in order to
not confuse CallKit (it misbehaves otherwise).

Updates LJM in order to stop printing few obsolete error messages.

Use subscribers to detect state change and emit those
out to other participants. Use middleware to register
the command listener.

This reverts commit 9625be1db3.

Otherwise it can eat clicks on elements it is above,
like YouTube and Etherpad controls.

Ever since we switched to handling track events instead of mute actions this has
been dead code. It was also added in the wrong place, since it's responsibility
of the JS code to solve the ping-pong problem.

While that option should default to true, let's be explicit about it.

The chat icons are different on windows and mac, with
windows icons being bigger. By settings a specific
width on the smiley container, windows would see
part of the smiley cut off.