Reuse pre-commit hook and information

[henri-egger]

I added the pre-commit hook for husky with the behavior as discussed in the old PR, it will check for compliance before the npm lint as it is usually faster and only if the reuse-helper-tool is installed, if not it will only print a warning.

I also added documentation in README.md as well as in guideline.md

[gappc]

@henri-egger thank you for your work.

Before merging, I think we need to clarify how to integrate reuse into the development and build process (see also discussion at the bottom of #386). It seems that the reuse-tool depends on either Linux, Python or Docker. We need to find ways to support those options or at least put some hint that those options exist at all and some information on how one could use Python / Docker for the pre-commit hook

[henri-egger]

@gappc no need to merge yet until we haven't decided on what to do eventually, but just in the meantime i made the pre-commit-hook also work on windows via python.

[gappc]

@henri-egger nice work, although I think that the pre-commit hook is not fixed for Windows but for Python (see also comment on your other PR)

[henri-egger]

@gappc I applied the changes you proposed, let me know what you think.

[gappc]

@henri-egger very good work, thank you :+1: