Added CallKit, Speaker and Application device orientation lock

[raosanat]

Purpose

Add support to demonstrate :

1. CallKit implementation in the ACS SDK.
   • Using CallClient.reportToCallKit(with:, cxproviderConfig:, completionHandler:) when app is in killed state.
   • Using createCallAgent(userCredential:, options:, cxproviderConfig:) to use the CallKit in SDK.
2. App is locked to portrait orientation mode and local video preview should not rotate.
3. Support for the app to work with both Beta and GA builds.
4. Register for push notification and handle push notifications.

Does this introduce a breaking change?

[ ] Yes
[x ] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[ x] Feature
[ ] Code style update (formatting, local variables)
[x ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Get the code

• Generate a token and replace in code line 22.

• Test the code

  1. Launch the app and then kill the app and place incoming call. App will use `reportToCallKit` api when push notification is recieved and then CallKit incoming call notification will be received.
  2. Test basic incoming and group join scenarios.

What to Check

Verify that the following are valid

• ...

Other Information