Fix bug with 2cb6400773

The problem was that we failed to escape the dash in the regexp,
meaning that it was matching all characters from “.” to “_”.

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

@@ -18,7 +18,7 @@ exports.types = {inline: true};
 exports.init = function(parser) {
 	this.parser = parser;
 	// Regexp to match
-	this.matchRegExp = /~?\$:\/[a-zA-Z0-9/.-_]+/mg;
+	this.matchRegExp = /~?\$:\/[a-zA-Z0-9/.\-_]+/mg;
 };
 
 exports.parse = function() {