Change logging level for 'oslo_db'
Change logging level for 'oslo_db'

Currently, running a command such as 'nova-manage' produces a lot of
irrelevant debug messages from the 'oslo_db' module. For example:

  $ nova-manage vm list
  instance   node            type       state      launched ...
  2015-10-29 15:20:32.624 DEBUG oslo_db.api [req-0fc5d653-a78f-44...
  ...
  test1      nova-dev        m1.tiny    active     2015-10-29 ...

Change the default logging level for this module to ensure this output
is not shown.

Change-Id: I85d4f18b7d32d9e2cbac22e075c435b7c84e7020
Closes-bug: #1343697

mikalstill/nova,rahulunair/nova,cernops/nova,jianghuaw/nova,phenoxim/nova,vmturbo/nova,vmturbo/nova,jianghuaw/nova,cernops/nova,Juniper/nova,klmitch/nova,mahak/nova,bigswitch/nova,BeyondTheClouds/nova,Juniper/nova,hanlind/nova,mikalstill/nova,openstack/nova,rahulunair/nova,klmitch/nova,gooddata/openstack-nova,klmitch/nova,mahak/nova,NeCTAR-RC/nova,BeyondTheClouds/nova,rajalokan/nova,alaski/nova,rajalokan/nova,Juniper/nova,bigswitch/nova,zhimin711/nova,cloudbase/nova,alaski/nova,rajalokan/nova,mikalstill/nova,sebrandon1/nova,hanlind/nova,hanlind/nova,openstack/nova,BeyondTheClouds/nova,zhimin711/nova,vmturbo/nova,gooddata/openstack-nova,phenoxim/nova,cloudbase/nova,jianghuaw/nova,dims/nova,CEG-FYP-OpenStack/scheduler,openstack/nova,Juniper/nova,gooddata/openstack-nova,mahak/nova,cyx1231st/nova,CEG-FYP-OpenStack/scheduler,gooddata/openstack-nova,sebrandon1/nova,cernops/nova,rajalokan/nova,klmitch/nova,NeCTAR-RC/nova,cyx1231st/nova,rahulunair/nova,dims/nova,cloudbase/nova,jianghuaw/nova,sebrandon1/nova,vmturbo/nova