glance v2 image sharing tests

Adding basic v2 glance image sharing tests
 * accepting image
 * rejecting image
 * owner cannot change membership status [negative]
 * trying to set invalid status [negative]

Fixing bug #1201136

Change-Id: Ic2f7102b64fc9dc1954b1e569d261baaaac9a184
Add special serial smoke option

We want smoketests to be parallel by default (for grenade etc), but that won't work
for neutron, so add a special case. Since we don't want to break
anything making this switch, it has to be done in 3 steps:

1) this patch
2) make neutron use smoke-serial
3) change smoke to be parallel

Change-Id: I03ded120c0b496026e39f14f6715624a91ac7558
Merge "Add special serial smoke option"
Merge "glance v2 image sharing tests"