Asking feature: filter locales in web interface

[cleargoal]

Thank you for this great package!

I'm using a few locales in the project, but from some package, a lot of them came.
I don't want to remove unused locales, because a part of them will be added to the project later.

Probably this may be useful not just for me, to have a locales filter in the web interface. Or, maybe to have active locales set in config.