change a small bit in the way valididy error messages get initialized

* parserInternals.c: change a small bit in the way valididy
  error messages get initialized
* python/TODO python/libxml.c python/libxml2-python-api.xml
  python/libxml2class.txt python/libxml_wrap.h python/types.c:
  added some memory debugging to track leaks at the libxml2 level
* python/tests/*.py: changed all tests to check for leaks,
  there is just one left in XPath extension registrations.
daniel
diff --git a/python/tests/push.py b/python/tests/push.py
index 738d3e9..5b60a16 100755
--- a/python/tests/push.py
+++ b/python/tests/push.py
@@ -2,6 +2,9 @@
 import sys
 import libxml2
 
+# Memory debug specific
+libxml2.debugMemory(1)
+
 ctxt = libxml2.createPushParser(None, "<foo", 4, "test.xml")
 ctxt.parseChunk("/>", 2, 1)
 doc = ctxt.doc()
@@ -22,4 +25,11 @@
     doc.freeDoc()
     i = i -1
 ctxt=None
-print "OK"
+
+# Memory debug specific
+libxml2.cleanupParser()
+if libxml2.debugMemory(1) == 0:
+    print "OK"
+else:
+    print "Memory leak %d bytes" % (libxml2.debugMemory(1))
+    libxml2.dumpMemory()