Added maximum distance to WlzDistanceTransform().
Split surrounds into tangential and non-tangential surrounds.
Fixed doxygen doc.
Fixed doxygen doc.
Fixed doxygen doc.
Fixed doxygen doc.
Added use of MathJax to render mathematics.
Split surrounds into tangential and non-tangential surrounds.
Split surrounds into tangential and non-tangential surrounds. Fixed doxygen doc.
Fixed leak from empty planes.
Cleaned code. Fixed leak of boundary lists.
Fixed leak caused by multiple returns for special cases.
Make sure all objects are freed.