Update oslo

This updates Oslo to the latest commit
997ab2776c9cad033234e28a92fb7bc0ef5bc4c0

It removes the test_service test file, as the behavior of restarting on
SIGHUP is dependent of openstack.common.service which has changed
recently, is already tested as part of oslo.incubator's tests.

Change-Id: I389c690f4febe9c69c1e2c39cd16961635469c75
Merge "Update oslo"