Add version string to i18n jsons for easier versioning

@rapl42 @mlbn33 @jsar97 @tmch74 @dbrb56 @pgrg81 @aaln02 @mblt41 @mczj84 An idea that just came to me: We could add a toplevel field to the i18n json files for easier versioning instead of relying on diff. Well for the time at least until we we have a proper localization service up an running. This way we could easily determine, even in app with a few extra lines, if the loaded version is the correct one. Maybe we could add it server side. I am thinking of a small php script (@mlbn33 you know this stuff better than me), that could splice the date of change of the actual json file (as provided by the servers file system) as a field into the json stream. Please discuss! 😅

P.S.: I know this is just a workaround, but at least in my opinion this could provide a bit of improvement until we have a better solution.