Bank servo module

SetBankLevel: takes left and right bank level, returns nothing
	local variables left level, right level
	scale local variables so that min/max bank level = lower/higher servo count
	if left and right bank levels between $0-$3000
		move left servo to left level, right servo to right level
	else if left bank level > $3000 and right bank level between $0-$3000
		move left servo to max left level, right servo to right level
	else if left bank level between $0-$3000 and right bank level > $3000 
		move left servo to left level, right servo to max right level
	else
		improper bank inputs