removed a warning more cleanup, added ENTITY and ENTITIES support

* tree.c: removed a warning
* xmlschemastypes.c: more cleanup, added ENTITY and ENTITIES
  support
* check-relaxng-test-suite.py check-xsddata-test-suite.py:
  cleanup/improvements of the regression tests batch
* test/relaxng/testsuite.xml: augmented libxml2 own testsuite
Daniel
6 files changed