* Moved Slate.h into SlateBasics.h and began shifting less commonly used headers into SlateExtras.h.
* Slate.h now simply includes SlateBasics.h and SlateExtras.h.
* Slate.h includes a deprecated warning now to indicate that SlateBasics.h + specific includes should be used instead.
* Moved dozens of inlined functions using Slate widgets into .cpp files to avoid header dependencies.
* All code samples now include SlateBasics.h and SlateExtras.h so future shifts will not break most those projects, but not trigger the deprecation warning of including Slate.h.
#BUN
[CL 2329610 by Wes Hunt in Main branch]
- Add Google Play support on Android
- Add editor settings for Google Play - enabled/disabled, and the app id for the games service
- Hack in Google Play leaderboards, including blueprint support, proper online subsystem implementation will come in the future
- These leaderboards work in TappyChicken
#codereview josh.adams, jj.hoesing, michael.noland
[CL 2050175 by Ryan Gerleve in Main branch]