added play to test some motion control ideas

find it in test_plays/MotionControlPlay.{hpp, cpp}
worked on a test play for bang-bang motion

doesnt quite work yet, but is mostly done
Change startTime to use a uint instead of a float
working on motion control play
Merge branch 'master' into motion-control-play
Worked on MotionControlPlay

* added configs for p,i,d (need to tune them)
* cleaned up unused stuff
changed default pid parameters for mc play
refactored motioncontrol play

it can now be used with arbitrary paths
refactored and added a new path

* added a circular path type
* refactored motion profile stuff into trapezoid()
* split PID into x and y
switched to PID control on position
cleanup motion control play
more motion control play work
DID A TON OF MOTION CONROL WORK
added Path.evaluate()
started adding angle path
did a bunch more motion control
removed a bunch of old motion control stuff
Added using the trapezoid method to the Path class.
added setting the robot start moving time.
Added the triangle case