Send missing translations in default locale only
If the default locale is already translated, its value will not be overwritten when encountering a missing translation in another language.
Merge pull request #1 from danielkman/feature/Send-default-translations-in-default-locale-only

Do not overwrite existing translations when encountering a missing one in a different locale
Strip the :default param from missing translations when current locale isn't the default locale
Merge branch 'refs/heads/pr99'