This adds a script `check-strings` that checks whether strings, such as file paths or class names, are valid in files outside of the source code, e.g. in translations or themes. This also adds a verify script to verify `check-strings` on a constant git commit. Both scripts are under CI.
test-files and their MD5 sums go here 16a41b09841f6893c6a621f3e7c63692 emptyproject.wav