I don’t think we would merge this, considering that SAFE Launcher was rewritten in React.js. Also, since we’re planning to move to SAFE Authenticator, it would probably be best to wait for that before starting to work on translations 
For SAFE Authenticator, we are starting with internationalization support right from the start. We will have to keep adding the language files into the locales folder and the addon should be able to pick them up from there: https://github.com/maidsafe/beaker-plugin-safe-authenticator/tree/master/locales