Remove the old parser code

Thus introducing a few functional regressions, but it's going to be
easier to fix things up without the old code knocking around and
getting in the way.

core/modules/parsers/wikiparser/rules/styleblock.js

@@ -42,7 +42,7 @@ exports.init = function(parser) {
 };
 
 exports.parse = function() {
-	var reEndString = "$@@(?:\\r?\\n)?";
+	var reEndString = "^@@(?:\\r?\\n)?";
 	var classes = [], styles = [];
 	do {
 		// Get the class and style