fixed the behaviour of node() patter which didn't patch the one defined in

* libxslt/pattern.c: fixed the behaviour of node() patter which
  didn't patch the one defined in XPath :-( . Closes bug #95793
* tests/docs/Makefile.am tests/docs/bug-92.xml
  tests/general/Makefile.am tests/general/bug-92.*: added the
  example in the regression tests for this case
Daniel