Switched all the processing to compiled XPath form, there is a

Switched all the processing to compiled XPath form, there is a
small problem showing up in the mediaobject.filename template of
DocBook, but the way unparsed-entity-uri() doesn't follow the spec
it seems so ...:
- xsltutils.h: cleanup some garbage added last night
- xsltInternals.h variables.c transform.c templates.[ch]
  preproc.c pattern.c keys.c: switched the whole XSLt processing
  to use XPath precompiled expressions and reusing them.
- functions.c: some cleanup, seems people don't use
  unparsed-entity-uri() the way it's supposed to be used
Daniel