libxml now grok Docbook-3.1.5 and Docbook-4.1.1 DTDs, this

popped out a couple of bugs and 3 speed issues, there is only
on minor speed issue left. Assorted collection of user reported
bugs and fixes:
- doc/encoding.html: added encoding aliases doc
- doc/xml.html: updates
- encoding.[ch]: added EncodingAliases functions
- entities.[ch] valid.[ch] debugXML.c: removed two serious
  bottleneck affecting large DTDs like Docbook
- parser.[ch] xmllint.c: added a pedantic option, will be useful
- SAX.c: redefinition of entities is reported in pedantic mode
- testHTML.c: uninitialized warning from gcc
- uri.c: fixed a couple of bugs
- TODO: added issue raised by Michael
Daniel

testHTML.c

@@ -572,7 +572,8 @@ xmlSAXHandlerPtr debugSAXHandler = &debugSAXHandlerStruct;
  ************************************************************************/
 
 void parseSAXFile(char *filename) {
-    htmlDocPtr doc;
+    htmlDocPtr doc = NULL;
+
     /*
      * Empty callbacks for checking
      */