Internationalization

[joergreichert]

Current state: LeipzigGiesst is only available in German.

Motivation: Cities become more international by students, refugees, etc. So to overcome language barriers (and to be honest watering trees doesn't require too much communication), the app texts and labels should be provided in different languages as well (English but maybe also languages, whose speaker may not firm with English).

Future state: There is drop down (resp. toogle button) to change the language to at least English.