virt: Move generic virt tests to nova/tests/virt/

In the interest of better organization, this patch moves generic virt testing
code into nova/tests/virt.

Change-Id: I79473726a848f0abbcb13865efe30e02aea09ae5
Better error message on malformed request url

The existing error message just said 'malformed url' which isn't
super-helpful. The new version expalins that the project ID in the URL is not
matching what's being passed in with the context.

Change-Id: I8e5b71fcd51ab3628425b53356f9671f3a2402c0
Merge "Better error message on malformed request url"
Merge "virt: Move generic virt tests to nova/tests/virt/"