1. Changed definition of IsDetached property in SR.cs: SR is detached when it has no PBDs or when all its PBDs are unplugged.
2. Added bool HasPBDs property in SR.cs (replaced previous IsDetached property definition).
3. Reviewed all usages of sr.IsDetached property.
Signed-off-by: Adrian Jachacy <Adrian.Jachacy@citrix.com>
Added a smoke test category and assigned a selection of tests to this category
to get a broad coverage of XenCenter functionality which can be used to quickly
test XenCenter works on a given platform