some cleanups extended the document to cover RelaxNG and tree operations

* relaxng.c: some cleanups
* doc/xmlreader.html: extended the document to cover RelaxNG and
  tree operations
* python/tests/Makefile.am python/tests/reader[46].py: added some
  xmlReader example/regression tests
* result/relaxng/tutor*.err: updated the output of a number of tests
Daniel

python/tests/reader4.py

@@ -0,0 +1,45 @@
+#!/usr/bin/python -u
+#
+# this tests the basic APIs of the XmlTextReader interface
+#
+import libxml2
+import StringIO
+import sys
+
+# Memory debug specific
+libxml2.debugMemory(1)
+
+def tst_reader(s):
+    f = StringIO.StringIO(s)
+    input = libxml2.inputBuffer(f)
+    reader = input.newTextReader("tst")
+    res = ""
+    while reader.Read():
+	res=res + "%s (%s) [%s] %d\n" % (reader.NodeType(),reader.Name(),
+				      reader.Value(), reader.IsEmptyElement())
+	if reader.NodeType() == 1: # Element
+	    while reader.MoveToNextAttribute():
+		res = res + "-- %s (%s) [%s]\n" % (reader.NodeType(),
+						   reader.Name(),reader.Value())
+    return res
+    
+expect="""1 (test) [None] 0
+1 (b) [None] 1
+1 (c) [None] 1
+15 (test) [None] 0
+"""
+
+res = tst_reader("""<test><b/><c/></test>""")
+
+if res != expect:
+    print "Did not get the expected error message:"
+    print res
+    sys.exit(1)
+
+# Memory debug specific
+libxml2.cleanupParser()
+if libxml2.debugMemory(1) == 0:
+    print "OK"
+else:
+    print "Memory leak %d bytes" % (libxml2.debugMemory(1))
+    libxml2.dumpMemory()