fixed servo value change lock

I added a lock out if a sorted servo value was out of order. THis
happened when a value was changed during the pulse cycle. I changed it
to use a copy of the data array instead.
Change the data storage of sorted data into its own array

This allows the position to stay constant through one servo cycle.
Before this if a servo position was changed whail in a cycle, the sorted
array would become unsorted.
stabilized the hysteresis calibration

I removed the center re-calculation from the bounding measurement. This
allows the upper and lower hysteresis to be different relative to the
center.