Dreamweb monitor commands translation

This pull request add the possibility to translate the monitor commands in dreamweb. Both the english and the translated commands are recognized.

SimSaw (who made that suggestion to me on IRC) confirmed that in DOSBox only the English commands are recognized for all game languages. So this pull request changes the behaviour from the original interpreter, which is one of the reason I am using a pull request rather than push directly (i.e. to give the possibility to the engine authors to voice their opposition to this change).

The rest of the monitor text is translated in the localized versions of the game. So it makes sense to also localize the commands in my opinion (as long as the english commands are still recognized).

Another reason I am using a pull request is that this is not the only way to do this. This commit uses the translations manager, so it will use the current GUI language, which may be different from the current game language. Instead we could store the French, German and Spanish translations for those commands directly in the engine (i.e. static array as for the english commands) and use them depending on the game language.