Don't wrap Glance exceptions in NovaExceptions

Exception objects from glanceclient are not serializable
in Nova and shouldn't be directly wrapped inside NovaExceptions.
The glanceclient portions of Nova that translate from Glance
to Nova should be creating new corresponding exceptions
independent of the Glance counterparts.

Change-Id: Ifbe992796f8c5738ae350617d41a9c312fa8ab94
xenapi: set vcpu cap to ensure weight is applied

There is a bug in XenServer 6.1 and 6.2 that means the vcpu weight
we set is ignored if the cap is not also set.

Setting the cap to its default of 0, meaning no cap, to ensure the
weight value is applied.

Fixes bug 1213960
Change-Id: I367a9afe188734cf5e95c01fc014b9044003d6e3
VMware: Fix bug for root disk size

The code would not configure the root disk size to that specified
in the flavor. This was always the size of the glance image.

Fixes bug: 1226052

Change-Id: I75ea766e3c96a2e0ad8a8d7cf7d24d80e1f94050
Fix processutils.execute errors on windows

Added a check for existence of geteuid.

This fix is related to oslo-incubator commit:
d6a963e911b8456c06dceb5ee3cc88a70c08bf82

Closes-Bug: #1209410

Change-Id: Ibaa1f061bf161768890d4708dc945180121726f9
Merge "xenapi: set vcpu cap to ensure weight is applied"
Merge "VMware: Fix bug for root disk size"
Merge "Don't wrap Glance exceptions in NovaExceptions"
Merge "Fix processutils.execute errors on windows"
Add MidoNet VIF driver