There are still issues, especially with "gnt-instance modify" and
resetting values. However, this is a start.

Reviewed-by: ultrotter

To my knowledge they're used nowhere and it's at least slightly
confusing to people adding new QA checks.

Reviewed-by: ultrotter

This patch removes the options that allow to create local_raid1 or
remote_raid1 instances. It also modifies the documentation and removes
these disk templates from burnin and from qa.

Reviewed-by: imsnah

Reviewed-by: imsnah

Reviewed-by: iustinp

This patch allows the selection of the hypervisor type for the QA
process; this is useful when testing hypervisor-independent changes that
don't require a Xen setup.

The patch also fixes the OS name in the sample QA config file provided.

Reviewed-by: imsnah

Reviewed-by: iustinp

Reviewed-by: schreiberal

Reviewed-by: schreiberal

Also check whether file contents are correct for both “gnt-cluster command” and
“gnt-cluster copyfile”.

Reviewed-by: iustinp

Added tests:
- “gnt-cluster getmaster”
- “gnt-cluster version”
- “gnt-instance list”
- “gnt-instance reinstall”

Reviewed-by: schreiberal

Reviewed-by: iustinp