sort the subclasses of a class in classIndex.html. fixes http://twistedmatrix.com/trac/ticket/1641
sort the subclasses of a class in classIndex.html.
fixes http://twistedmatrix.com/trac/ticket/1641

hawkowl/pydoctor,chevah/pydoctor,jelmer/pydoctor,chevah/pydoctor,hawkowl/pydoctor,jelmer/pydoctor,jelmer/pydoctor