[Libvirt-cim] [PATCH 0 of 4] Add clock offset support

[Dan Smith]

This patch set adds the ability to control the clock offset of a guest from
the CIM providers, which is important with dealing with Windows guests.  It
gives us:

- The ability to specify the offset during DefineSystem
- The ability to inspect the offset in the VSSD object
- The knowledge of the <clock> element in libvirt XML so as not to clobber it
  when adjusting the XML as part of another action