Add more languages to translations

[mueller-ma]

Hi,
in some other projects I noticed that people don't always ask for a new language to be added to Crowdin, but rather wait until it's available some day. Thus I recommend to add some more languages to the Crowdin project.
Maybe the same than for the Android app?

A badge in the Readme would increase the visibility of Crowdin. You can get the code for a badge by clicking on the badge on https://crowdin.com/project/openhab-ios/settings#translations.