Redesign code to enable multiple high-level maneuvers

[hmartiro]

We want to be able to

• Walk forward, and turn while doing it
• Walk backward, and turn while doing it
• Turn in place
• Go up stairs
• Pronk?

Right now, the code is too centered around a forward walk. It needs to be redesigned to be more modular and support these different patterns. Also need to think about how to handle key holding vs tap mode better. Maybe just ditch holding and go purely tap mode?

[hmartiro]

Made a lot of progress on this front:

• Checking for keyup events was eliminated - it's tapmode only right now, WASD.
• Forward and backward walking functions were combined into the startTripod, tripodFrame, and stopTripod functions and these were condensed further
• Some new parameters made and standardized names for stuff
• Mounted vs not mounted is no longer a variable, but a command line argument. Call xjus mounted or python xjus.py mounted to get the mounted stand angle

Things to be done:

• Change turning to only subtract from the ground angle, never add (or only a bit)
• Implement turning in place
• Implement leg cycle walking (and try it with four legs)
• Implement stair gait
• Implement pronking
• Implement accelerating gait (need to improve communication speed for this, need to have chunksize down near 1)