HFJ-187: Added new api functions for outputting generic copyright information for content.
Should not break anything.
HFJ-187: Fixed copyrights for cp, audio and image.
HFJ-187: Added thumbnail for image.
HFJ-187: Fixed single copyrights for media. Multiple makes no sens.
HFJ-187: Fixed copyrights for boardgame and libraries used there.
Added README files.
Merge branch 'master' of github.com:h5p/h5p-image

Conflicts:
	README.md