There is no reason for them to run on the main thread, it's safe to call
AVFoundation functions on threads other than the main thread.
The previous code made an incorrect claim about the thread in which the audio
route change notification selector is called: it's called on a secondary thread:
https://developer.apple.com/documentation/avfoundation/avaudiosessionroutechangenotification
Fixes the following warning:
~~~
Module XXX requires main queue setup since it overrides `constantsToExport` but doesn't implement `requiresMainQueueSetup`. In a future release React Native will default to initializing all native modules on a background thread unless explicitly opted-out of.
~~~
For AppInfo and AuioMode, there is no need to initialize anything in the UI
thread, so just return NO.
1. Aligns the project structure of Jitsi Meet SDK for iOS with that for
Android for better comprehension.
2. The command `react-native run-ios` uses the last Xcode project or
workspace in the list of these sorted in alphabetical order. Which
limits our freedom in naming. Thus having only an Xcode project in
the root directory of the iOS project structure gives us back the
freedom in naming.
3. Allows the Podspec to work for the app project in addition to the sdk
project because we need Crashlytics in the app which is integrated
via Cocoapods as well.
4. Further removes references to JitsiKit in the source code for the
sake of consistent naming.