Changelog:
- Change ladder to be in player state component
- Add ladder state transition
- Hold up or down to enter ladder when overlap with ladder
- On ground, ladder has to be on foot
- Either jump or exit a ladder to exit ladder state
- Ignore external forces during ladder state
- Ladder uses velocity instead of acceleration to move player
- Reduce jump speed if not on ground (such as on ladder)
- Make water transparent, finally