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

include/libxml/entities.h

@@ -54,6 +54,8 @@ struct _xmlEntity {
     const xmlChar    *ExternalID;	/* External identifier for PUBLIC */
     const xmlChar      *SystemID;	/* URI for a SYSTEM or PUBLIC Entity */
 
+    struct _xmlEntity     *nexte;	/* next entity in the hash table */
+
 #ifdef WITH_EXTRA_ENT_DETECT
     /* Referenced entities name stack */
     xmlChar           *ent;             /* Current parsed Node */