Doc fix.
Documentation fix.
Include the language as part of a rollback copy.

This prevents us from running the language change code whenever we
do a rollback when a non-default language is enabled.

Fixes #73.
Fix compatibility between OldMoveTransition and define.move_transitions.

Fixes #74.
Doc fix.
Change how we compensate for times in a restarted move transition.

The previous method was causing problems where when we created
a new screen under a transition, the new screen would get the
wrong creation time.
Stop ongoing transitions when we enter a new context.

A minor performance improvement, which also prevents the side-effects
of the new code being surrounded by old transitions.
Bump version.
Document renpy.input.
Allow the music room to loop tracks, rather than advancing them.
Fix doc typos.

Thanks, Koichi.
Merge branch 'master' into android
Improve OpenGL ES2 support.