Add Documentation in Markdown plus express middleware for in-site rendering.

res/app/settings/language/language-service.js

@@ -4,6 +4,8 @@ module.exports = function LanguageServiceFactory(
   SettingsService
 , gettextCatalog
 ) {
+  // TODO: make this LanguageProvider so it can be used on config
+
   var LanguageService = {}
 
   function detectLanguage() {