cleanup added class for parser context, added first cut for push mode

* python/Makefile.am python/types.c: cleanup
* python/libxml.c python/libxml.py python/libxml_wrap.h
  python/generator.py python/libxml2-python-api.xml
  python/libxml2class.txt: added class for parser context, added
  first cut for push mode support. Added a framework to generate
  accessors functions.
* python/tests/Makefile.am python/tests/push.py: added a push
  test
Daniel
diff --git a/python/tests/Makefile.am b/python/tests/Makefile.am
index 79d5456..b8e9cec 100644
--- a/python/tests/Makefile.am
+++ b/python/tests/Makefile.am
@@ -4,6 +4,7 @@
     tst.py	\
     tstxpath.py	\
     xpathext.py	\
+    push.py	\
     error.py	\
     xpath.py
 
@@ -20,6 +21,9 @@
 tests:
 endif
 
+clean:
+	rm -f *.pyc core
+
 install-data-local:
 	$(mkinstalldirs) $(DESTDIR)$(EXAMPLE_DIR)
 	-(for test in $(TESTS) $(XMLS); \