use frame normalization for effect.
Explicit null check to avoid bool conversion of 0
Merge pull request #34 from alancutter/zeroStartTime

Explicit null check to avoid bool conversion with 0
Merge pull request #35 from shans/animConsRevisit

use frame normalization for effect.
player discarding
check finished
Merge pull request #36 from tim-loh/playerdiscarding

player discarding
Basic implementation of finish events
Add event object and addEventListener()
Add additional tests