Issue 799 easessions close on disconnect

[kmicha19-ford]

Fixes smartdevicelink#1799 (when used in conjunction with #2)
Fixes smartdevicelink#1809
Fixes smartdevicelink#1892
Fixes smartdevicelink#1893

This PR is ready for review.

Risk

This PR makes no API changes.

Testing Plan

• I have verified that I have not introduced new warnings in this PR (or explain why below)
• I have tested this PR against Core and verified behavior.

Unit Tests

Unit tests were updated for the refactored classes.

Core Tests

• Built the Obj-C example app and verified that all interactions work
  • iAP disconnect / reconnect
  • LockScreen on/off rapidly
• Built the Swift example app and verified that all interactions work
  • iAP disconnect / reconnect
  • LockScreen on/off rapidly

Summary

• Refactors iAPSession code that uses the Apple External Accessory Frameworks to create, open, use, and close EASessions.

Changelog

Breaking Changes

• None

Enhancements

• Moves all managment of EASession creation, open, and closing into a single class, SDLIAPSession
• Eliminates the use of NSThread from SDLIAPDataSession
• SDLIAPSession now uses a DispatchQueue to provide the required thread for EASession
• Uses composition instead of inheritance, SDLIAPControlSession and SDLIAPDataSession now use SDLIAPSession instead of being subclasses of it
• Provides a short simple code path for closing EASessions
• Eliminates over two hundred lines of code

Tasks Remaining:

• More unit tests

CLA

• I have signed the CLA

[kmicha19-ford]

Will do this PR again today.

[NicoleYarroch]

I think a few things were missed from my last review. Can you tag me when you have a fix for the crash I noted in the last review? Thanks!

Sorry, left this review on the wrong PR