Assign defaults for owners of the file blockdevice

The implementation code expects owner and group to be filled in.  This
is fully backwards compatible.
Merge pull request #15 from piojo/blockdev-file-owner

Assign defaults for owners of the file blockdevice
Merge pull request #13 from piojo/simpler-client

Adapt the client RPM listings to the Yum-based SPMA
Merge pull request #5 from quattor/master

update