* relaxng.c xmlreader.c xmllint.c include/libxml/relaxng.h
  include/libxml/xmlreader.h: implemented streaming of
  RelaxNG (when possible) on top of the xmlReader interface,
  provided it as xmllint --stream --relaxng .rng .xml
  This seems to mostly work.
* Makefile.am: updated to test RelaxNG streaming
Daniel