Fix regressions introduced by CVE-2014-0191 patch

A number of issues have been raised after the fix, and this patch
tries to correct all of them, though most were related to
postvalidation.
https://bugzilla.gnome.org/show_bug.cgi?id=730290
and other reports on list, off-list and on Red Hat bugzilla
diff --git a/parser.c b/parser.c
index c0dea05..ba70f9e 100644
--- a/parser.c
+++ b/parser.c
@@ -2598,8 +2598,8 @@
 		    xmlCharEncoding enc;
 
 		    /*
-		     * Note: external parsed entities will not be loaded, it is
-		     * not required for a non-validating parser, unless the
+		     * Note: external parameter entities will not be loaded, it
+		     * is not required for a non-validating parser, unless the
 		     * option of validating, or substituting entities were
 		     * given. Doing so is far more secure as the parser will
 		     * only process data coming from the document entity by
@@ -2608,6 +2608,9 @@
                     if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
 		        ((ctxt->options & XML_PARSE_NOENT) == 0) &&
 			((ctxt->options & XML_PARSE_DTDVALID) == 0) &&
+			((ctxt->options & XML_PARSE_DTDLOAD) == 0) &&
+			((ctxt->options & XML_PARSE_DTDATTR) == 0) &&
+			(ctxt->replaceEntities == 0) &&
 			(ctxt->validate == 0))
 			return;
 
@@ -12616,6 +12619,9 @@
 	return(NULL);
     }
 
+    /* We are loading a DTD */
+    ctxt->options |= XML_PARSE_DTDLOAD;
+
     /*
      * Set-up the SAX context
      */
@@ -12743,6 +12749,9 @@
 	return(NULL);
     }
 
+    /* We are loading a DTD */
+    ctxt->options |= XML_PARSE_DTDLOAD;
+
     /*
      * Set-up the SAX context
      */