App Guide translatable step content and translatable button captions

[sjorsschultz]

Is your feature request related to a problem? Please describe.
For a multi-language app users with different language settings all see English button captions and same step content

Describe the solution you'd like
Make configuration, content and button captions of widget translatable by adjusting language settings in Studio Pro.

Describe alternatives you've considered
Content is translatable with a workaround by passing $Language as contextparameter in string expression, but should be easier by just adjusting language in Studio Pro.