Added brake function for H bridge controller

added two functions brakeSet() and brakeRelease(). These will set the
and release the brake at a specified throttle percent
Incorporated attachInterupt() function

this did not work as it created a race condition. The first interrupt
would stop the 2nd interrupt from finishing.
Revert "Added brake function for H bridge controller"

This reverts commit 7d176a076e6f96ce36056922b6eabe071fced5a7.