Presenter Remote app communication improvements

Fix: Removed false error reports when connecting to CCLI / SongSelect
Fix: Improved media import error reporting
Change: Added option to Launch PowerPoint, even if display scale isn't set correctly

Fix: Mobile stage display now supports text version only slides

Fix: Fixed connection timeout issue when keeping Presenter open for long periods of time.

Fix: Google Slides authentication fix. Google Slides are now chosen through Google Picker, only giving Presenter access to selected presentations.