Improve support for internationalization.

Currently there are a few different languages available to choose from in the application and at least the Spanish one is incomplete (several strings untranslated, things wrongly translated), but the thing that can't be happening is the way a language is changed in the application: the program needs to be closed for it to change its localization, which is not wrong per se, only you should notify of the user that it's going to restart (or tell the user that the next time he/she starts the program it'll be in the new language) but it should NOT restart if an open session is in progress!

As of now if you change the language when remote controlling a machine the program restarts itself without any warning closing the control session.