Merge branch '342-organise-strings-xml-to-make-life-easier-for-translators' into 'master'

Group strings and remove unused resources

Before I grouped the strings, I removed unused resources as well to not group things that are not being used anymore.

The grouping tries to follow a normal usage lifecycle of the app where the user works their way down the navigation drawer and explores all features in one area.

Closes #342

See merge request !277