Add Rule.parser property for custom rules to specify which Markdown parser output they use, honor it strictly, and add full type support.

lib/md039.js

@@ -13,6 +13,7 @@ module.exports = {
   "names": [ "MD039", "no-space-in-links" ],
   "description": "Spaces inside link text",
   "tags": [ "whitespace", "links" ],
+  "parser": "markdownit",
   "function": function MD039(params, onError) {
     filterTokens(params, "inline", (token) => {
       const { children } = token;