force releasenotes warnings to be treated as errors
force releasenotes warnings to be treated as errors

Per http://lists.openstack.org/pipermail/openstack-dev/2015-November/080521.html,
we need to make sure that there are no warnings for reno.

Change-Id: I50ce202f82e3213d07c3989780833e18b4c2bf08

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