borg2 commands: use repo*, not r*

[ThomasWaldmann]

https://github.com/borgbackup/borg/discussions/7647 as discussed / voted there (voting is / will be open until this ticket is close, so in case you missed it, you can still vote there).

Current state of repo-level commands:

borg rcreate
borg rlist
borg rinfo
borg rdelete
...

Change to:

borg repocreate
borg repolist
borg repoinfo
borg repodelete
...

[Ducasse]

THANKS a lot for your findings. I would explain why alain mentions problems with observeSlot. @plantec @tesonep @MarcusDenker

[Ducasse]

I do not understand what the assignment is not part of the ensure.