Merge Mylyn Docs Repository into Mylyn Repository

[BeckerFrank]

We have integrated the Mylyn Docs Repository into the Mylyn Repository.

The first Commit was 81e1520. So now short after Release of Mylyn 4.1.0 we want to archive Mylyn Docs Repository and have all Sources in the Mylyn Repository.

Further details can be found here

Help in completing the open tasks is welcome.

[olberger]

FWIW, this probably explains the " This repository has been archived by the owner on Dec 5, 2023. It is now read-only." mention on the repo at https://github.com/eclipse-mylyn/org.eclipse.mylyn.docs ... but without any redirection there :-/

Maybe it could be a good idea to add some kind of redirection message if it's not completely read-only yet