Add os-start/stop functional negative tests
Add os-start/stop functional negative tests

The negative tests of os-start/stop API are not covered enough
in functional tests. We want to add the conflict tests of when
this API runs in the unexpected state of server.
* Case of os-start API, the server status must be SHUTOFF.
* Case of os-stop API, the server status must be ACTIVE or ERROR.

Change-Id: I1c44ae737ad39bc58dd3ebfd554176d6400fd9fd

Juniper/nova,jianghuaw/nova,gooddata/openstack-nova,Juniper/nova,klmitch/nova,Juniper/nova,jianghuaw/nova,rajalokan/nova,openstack/nova,rahulunair/nova,rahulunair/nova,gooddata/openstack-nova,klmitch/nova,mikalstill/nova,jianghuaw/nova,phenoxim/nova,vmturbo/nova,hanlind/nova,openstack/nova,phenoxim/nova,vmturbo/nova,mikalstill/nova,gooddata/openstack-nova,mikalstill/nova,rajalokan/nova,hanlind/nova,openstack/nova,mahak/nova,vmturbo/nova,klmitch/nova,gooddata/openstack-nova,rajalokan/nova,vmturbo/nova,rajalokan/nova,jianghuaw/nova,rahulunair/nova,klmitch/nova,mahak/nova,hanlind/nova,Juniper/nova,mahak/nova