Support for spree_i18n language selector

[exoder]

This language selector doesn't fit and is looks bad:

And even like this:

[oleksify]

@exoder It's quite complicated to write styles for various situations like this. I think it's much easier to add some small styles on your own to make theme play nicely with enabled modules/translations.

But I agree, that language selector may look better in general. I'll take a look.