gnome-languages: Display of modifiers in Formats view

In the Formats view in g-c-c we display the options in reverse order, i.e.

Country (Language)

In case of a modifier it may now look like this:

Serbia — Latin (Serbian)

However, a modifier typically bears on the language rather than the country, so with this MR i propose a change so it looks like this:

Serbia (Serbian — Latin)

Other important examples:

Spain (Catalan — Valencia)
India (Kashmiri — Devanagari)

• Valencia is a dialect of Catalan as spoken in Valencia.
• Devanagari is a script which can be used to write Kashmiri.