added more cases for DELETE dist-datastore tests"
updated dist-datastore servlet to return proper 4xx and 202 messages for DELETE calls
fixed response code for datastore DELETE to 204 No Content
fixed response code for datastore DELETE to 204 No Content in Dist Datastore Servlet
fixed setting of response status for datastore delete call
Merge pull request #870 from rackerlabs/D-16712-datastore-delete

D 16712 datastore delete