PRUNING: GOLAY ALPHABET E
Macro: PROBMOTHIPRU
Function: To remove nuisance branching from skeletons. Obtained by thinning the image with structuring element 'E'.  
Parameters:
1. Input output image planes.
2. Struc element size (between -1 and 20).
-- (S): click with left mouse button along the slider item.
-- Size[ ](T): gives current size.
-- Cancel(B): click left mouse button to cancel operation.
-- OK(B): click left mouse button to confirm operation. 
