intersectLibrary   "intersect" 
Find Line Intersection X/Y coordinates.
Simple to use, will find intersection if it exists on the segments
if the line segments do not cross on segment, an 'na' value will be returned
if you plot  new items with the output coords,  they still plot.  
avoid this by  setting a na(x)   condition before plotting new items
 get(l1, l2, ( optional _round) ) 
  line intersection coordinates
  Parameters:
     l1 : (line)  first  line
     l2 : (line)  second line
     _round : True to make an INT for plotting
    if not used, will not round ( overload loophole)
  Returns:    with x as int if bool is used
