Log Message:
textproc/xxdiff-scripts: add xxdiff Python wrappers

xxdiff comes with a bunch of wrapper Python scripts that invoke xxdiff in
creative ways.  All this code is now distributed with xxdiff, in an xxdiff
Python package, which you can leverage to build your own file transformation
scripts around xxdiff. [from author http://furius.ca/xxdiff/#id10]