Support language dialects

[erny]

Transmeta get_real_fieldname only supports simple languages if language is not given. I would like to have fields like this one:

• help_ca-va, being ca-va the valencian dialect of the catalan language.

[goinnn]

@erny I think the same of you but this feature could break a lot of projects. @msaelices dislikes this feature for this reason.

[erny]

Well, I still had not the time to provide a patch, but I have one that I think won't break too much code. I will send a pull request.