New: Warning on generic Ajax error (404 etc)

- Previously DataTables would only show an error message if there was a
  JSON parsing error. However, if there was any other kind of error,
  such as a 404, it would just silently swallow the error. THink its
  best to show an error and a tech note.

.datatables-commit-sync

@@ -1 +1 @@
-ae0951bf93e1b87ced3c70ddf3a18ed3ae55277d
+4adf77363c60f233d2674e2eb2706032270c1839

media/js/jquery.dataTables.js

@@ -2224,8 +2224,13 @@
 			"cache": false,
 			"type": oSettings.sServerMethod,
 			"error": function (xhr, error, thrown) {
+				var log = oSettings.oApi._fnLog;
+	
 				if ( error == "parsererror" ) {
-					oSettings.oApi._fnLog( oSettings, 0, 'Invalid JSON response', 1 );
+					log( oSettings, 0, 'Invalid JSON response', 1 );
+				}
+				else {
+					log( oSettings, 0, 'Ajax error', 7 );
 				}
 			}
 		};