build.bat: Add support for MPCTestAPI
Update coverity.bat.

Add MPCIconlib and MPCTestAPI.
sign.bat: Retry when signing fails.
Show error message when toolset call fails.
Update Unrar to 5.0.0.14.
PPageShaders: remove refactoring leftover

CID 1135355
Reposition toolbars properly on media close
Option to delay playback after mode auto-switch

Fixes #3235