completely different fix for the recursion detection based on entity

* parser.c include/libxml/parser.h: completely different fix for
  the recursion detection based on entity density, big cleanups
  in the entity parsing code too
* result/*.sax*: the parser should not ask for used defined versions
  of the predefined entities
* testrecurse.c: automatic test for entity recursion checks
* Makefile.am: added testrecurse
* test/recurse/lol* test/recurse/good*: a first set of tests for
  the recursion
Daniel

svn path=/trunk/; revision=3783

include/libxml/parser.h

@@ -298,6 +298,7 @@ struct _xmlParserCtxt {
     xmlError          lastError;
     xmlParserMode     parseMode;    /* the parser mode */
     unsigned long    nbentities;    /* number of entities references */
+    unsigned long  sizeentities;    /* size of parsed entities */
 };
 
 /**