Merge branch 'redisplay_fix' into 'master'

Redisplay fix

Calling redisplay() multiple times per turn is notorious for causing lag. The worst offender is probably Smoke Bomb, and it just got stripped from Creeping Dark.
This commit introduces a new scheduleRedisplay method, which uses little-known feature of game:onTickEnd to ensure that a redisplay would only get called once per this tick, not causing any frame drops.