Do cleaning up resource before rescheduling.

Fix bug: #1153964

If some exception raised when spawn instance, the instance will be
rescheduled to other host. But just deallocate network before
rescheduling is not enough, like security group filters and volumes
will stay on old host.

So shutdown instance and clean up volumes instead of just deallocate
network before rescheduling.

Change-Id: Ieb6220ae66f0b97a92c50f6998f456968b516fcb
Add the serial to connection info for boot volumes

The serial parameter wasn't being added to volumes specified at
boot time. Added tests. Also cleaned up import in test_compute
to match the rest of the file.

Fixes bug 1148734

Change-Id: I05a623849680c5d0bb530fba4c4e6051d3b000aa
Fix system_metadata "None" and created_at values

The ill-fated migration 153 converted None instance_type values to
"None" in the database instead of properly making them NULL. This
corrects that by sweeping all of the likely instance_type_% values and
converting "None" to NULL. Also, it adds a belated created_at stamp
to all of the items, which was missing in 153 as well.

It also corrects the 153 migration to avoid polluting things in the
first place for systems that haven't rolled through that yet.

Fixes bug 1152546

Change-Id: I3585463ae15abfd534f2ff070e2974f3cb51d7e8
Don't include traceback when wrapping exceptions

The fix in fa52cb09b2270876c9d9a03106f961be6c9db834 strips tracebacks
from exceptions when returning them to the user, but it still spams
the log with a long traceback. We shouldn't be including the traceback
when we wrap the exception in the first place. Instead we just
include the message.

It also updates the error code to 409 for device in use since this
is actually a conflict.

Fix for:

  bug 1155315
  bug 1103324
  bug 1092610

Change-Id: I95019a3022eb52e0335c455009c13fe229475d03
Merge "Add the serial to connection info for boot volumes"
Merge "Don't include traceback when wrapping exceptions"
Merge "Fix system_metadata "None" and created_at values"
Merge "Do cleaning up resource before rescheduling."