Enhance usability of tag recognition and handling

Make the tags a bit smaller then the text and change their color. Goal: Color and proportions compared to the text should be the same as in Trados (see Screen, that Aleks provides).

Complaint by users: shortcut works but is quite slow: Sylvi evaluates, how Trados does work here and if we can take this over.
=> Result from Sylvi: The shortcut in Trados works similar and it should be user preference, if that is slow or what is better. Therefore we leave it for now as it is.