[DRBD-user] linstor-proxmox 4.0.0

[Roland Kammerer]

Dear Proxmox users,

as there have not been any serious complaints since RC2, let's finalize
this.

Changes:

* implement APIVER 2
* switch to REST-API
* Linstor: saner defaults for not set variables
* support APIVER 2 and 3 "on the fly"
* poll in_use before delete
* kvm: mark DRBD device as RW

Best, rck
 
[1] https://github.com/linbit/linstor-proxmox
[2] https://www.linbit.com/downloads/connectors/linstor-proxmox-4.0.0.tar.gz