Rename translation: fa_IR->fa and af_ZA->af.

These languages aren't really country-specific variants, so just use the base name.
Add Crowdin configuration file.

Manage translations on Crowdin.net.
Enable localization of Info.plist on OS X.

So far only two keys - names of translation files - are localized.

Also add to crowdin.yaml.
Update LetsMove.

The important part is modern naming of translation directories.
Upload LetsMove's MoveApplication.strings to Crowdin.
Merge branch 'use-crowdin' into stable
Install LetsMove's translations.
Merge branch 'stable' of github.com:vslavik/poedit into stable