Also:
- Moved queue drains outside of update loop.
- Better naming.
- Dirty flag after animations have been changed to avoid computing timelinesFirst more times than needed.
- Don't use timelinesFirst when mix == 1.
- Added `animationStart` so a portion of an animation can be looped.
- Changed timing fields to: trackTime, trackLast, trackEnd, animationStart, animationEnd, animationLast
- Removed default *Threshold fields. People can just set it on the track entry if they don't like the defaults.
- Removed `loopCount` from complete event. People can calculate it based on track time.
#621closes#535closes#593
- Renamed `previous` to `mixingFrom` for clarity.
- Added `trackEntry` method to fully initialize TrackEntry.
- Moved `mixDuration` initialization to happen when TrackEntry is initialized. This allows mix times to be specified (or changed) through the TrackEntry, without using AnimationStateData.
- Made EventQueue static to ease porting.
- Javadocs.
#621
