Physics bugs

[vinayg-usc]

• Player cannot jump high while on a platform going up
• Box is not bound to platform
• Box rotation to be disabled (like was done for player)
• Pushing the box off a platform was getting stuck

[vinayg-usc]

@EfazMuh - Can you help with these? Feel free to reassign/unassign #86 if you don't have time.

These bugs would take higher priority as our new levels require them.

[vinayg-usc]

Closed via #90