Contributer License Agreement / Developer Certificate of Origin

This MR adds the Developer Certificate of Origin and explains how contributors can agree to it (in Contributing.md).

Contributors need to run the contributing/hooks/setup_commit_msg_hook.sh script once at the root of the repository to ensure that their commits end with Signed-off-by. More explanation is in the contributing.md file.

Closes #261 (closed)

changed milestone to %Queue 1.0

added priomed statusdiscussion labels

approved this merge request

started a merge train

merged

mentioned in commit d2fd9684