Updates the copyright to 2021 for all files that have a copyright. Files in our source code without the copyright header still do not receive one automatically. Additionally, backlisted files are also excluded.
Previously the copyright of chiliproject which references redmine stated a copyright of redmine up to and including 2017 which is not true for the code we have in here. Because of that I changed that to 2013
Thereby permission checks will no longer silently fail if no user was
passed.
This uncovered a lot of places where we actually expected a user to be passed, when it wasn't.
This was especially true for collections.
The basic idea is, that virtually all representers could change their behaviour based on the current user.
Representers where this is not the case (e.g. Digest), can still explicitly opt-out.
Ivan Kuchin