Use oslo.notify for notifications

Change-Id: I5a88204202ae6bfd19bb12c4e068e88960683eee
Blueprint: oslo-notify
Merge "Use oslo.notify for notifications"
Code cleanup

Delete redundant modules from magnetodb.openstack.common

Blueptint: review-openstack-common
Change-Id: Ibc75f37cc73e3eb30dc40cf47696173510be7f87