Update German and English translations.
Add browsertests for customstyles form.
Implement custom styles adapter.
Refactor customstyles form to use custom styles adapter.
Let the customstyles adapter handle cache invalidation.
Implement genericsetup import.
Implement genericsetup export.
Generic setup import: support multiple files with pattern r'customstyles.*\.json'.
Merge pull request #47 from OneGov/jone-customstyles

Implement generic setup import / export steps for custom styles