Wrote new unit conversion methods

Added some fields to settings.c, and then wrote methods to convert
between inches, centimeters, and ticks. I also moved some old code out
of api.c.
Fixed main_teleop to use the correct method

setMovement was changed to take a raw value (0-100) and branched to
setMovementFrromJoystick to take a joystick value (0-128). Main teleop
has been updated to reflect the new method call.
Changed API instructions and updated to-do list