Make notifications properly string-convert instance datetimes
Make notifications properly string-convert instance datetimes

Instance objects use real datetimes for launched_at and terminated_at.
This patch makes the notification information function properly
handle those.

Related to blueprint compute-api-objects

Change-Id: I8622662a83ff0bdc75ffc9e267c5485925326f24

BeyondTheClouds/nova,double12gzh/nova,CEG-FYP-OpenStack/scheduler,j-carpentier/nova,ted-gould/nova,noironetworks/nova,gooddata/openstack-nova,devendermishrajio/nova,gooddata/openstack-nova,petrutlucian94/nova_dev,hanlind/nova,cloudbase/nova-virtualbox,Yusuke1987/openstack_template,ted-gould/nova,klmitch/nova,sebrandon1/nova,phenoxim/nova,spring-week-topos/nova-week,nikesh-mahalka/nova,barnsnake351/nova,Juniper/nova,bigswitch/nova,vladikr/nova_drafts,klmitch/nova,shail2810/nova,eonpatapon/nova,viggates/nova,noironetworks/nova,eharney/nova,jeffrey4l/nova,TwinkleChawla/nova,devendermishrajio/nova_test_latest,citrix-openstack-build/nova,petrutlucian94/nova,ewindisch/nova,devendermishrajio/nova,rickerc/nova_audit,cloudbase/nova,Metaswitch/calico-nova,yosshy/nova,qwefi/nova,belmiromoreira/nova,adelina-t/nova,CCI-MOC/nova,scripnichenko/nova,iuliat/nova,petrutlucian94/nova_dev,kimjaejoong/nova,BeyondTheClouds/nova,SUSE-Cloud/nova,silenceli/nova,shahar-stratoscale/nova,sebrandon1/nova,isyippee/nova,kimjaejoong/nova,leilihh/novaha,cloudbase/nova,citrix-openstack-build/nova,maelnor/nova,joker946/nova,dims/nova,jianghuaw/nova,leilihh/nova,vmturbo/nova,zhimin711/nova,virtualopensystems/nova,isyippee/nova,mmnelemane/nova,thomasem/nova,varunarya10/nova_test_latest,barnsnake351/nova,gooddata/openstack-nova,dawnpower/nova,redhat-openstack/nova,JioCloud/nova,scripnichenko/nova,CloudServer/nova,berrange/nova,bclau/nova,yatinkumbhare/openstack-nova,ntt-sic/nova,TwinkleChawla/nova,MountainWei/nova,ntt-sic/nova,cloudbase/nova-virtualbox,rajalokan/nova,rickerc/nova_audit,eonpatapon/nova,gooddata/openstack-nova,Juniper/nova,petrutlucian94/nova,varunarya10/nova_test_latest,shootstar/novatest,tanglei528/nova,OpenAcademy-OpenStack/nova-scheduler,dawnpower/nova,maelnor/nova,orbitfp7/nova,tianweizhang/nova,NeCTAR-RC/nova,dims/nova,Tehsmash/nova,raildo/nova,bclau/nova,saleemjaveds/https-github.com-openstack-nova,tangfeixiong/nova,LoHChina/nova,rahulunair/nova,SUSE-Cloud/nova,edulramirez/nova,ruslanloman/nova,devoid/nova,Juniper/nova,openstack/nova,orbitfp7/nova,mmnelemane/nova,angdraug/nova,takeshineshiro/nova,alexandrucoman/vbox-nova-driver,cloudbau/nova,hanlind/nova,BeyondTheClouds/nova,cernops/nova,takeshineshiro/nova,Francis-Liu/animated-broccoli,CloudServer/nova,alvarolopez/nova,zzicewind/nova,jianghuaw/nova,mikalstill/nova,mgagne/nova,edulramirez/nova,viggates/nova,mikalstill/nova,phenoxim/nova,NeCTAR-RC/nova,yosshy/nova,akash1808/nova,rrader/nova-docker-plugin,klmitch/nova,Yusuke1987/openstack_template,Tehsmash/nova,blueboxgroup/nova,projectcalico/calico-nova,fnordahl/nova,jianghuaw/nova,eayunstack/nova,affo/nova,j-carpentier/nova,devoid/nova,mandeepdhami/nova,imsplitbit/nova,fnordahl/nova,alaski/nova,Metaswitch/calico-nova,luogangyi/bcec-nova,alexandrucoman/vbox-nova-driver,projectcalico/calico-nova,virtualopensystems/nova,felixma/nova,openstack/nova,rahulunair/nova,rahulunair/nova,raildo/nova,hanlind/nova,bigswitch/nova,mahak/nova,badock/nova,Yuriy-Leonov/nova,blueboxgroup/nova,mandeepdhami/nova,JioCloud/nova,imsplitbit/nova,JianyuWang/nova,devendermishrajio/nova_test_latest,mgagne/nova,thomasem/nova,silenceli/nova,whitepages/nova,tanglei528/nova,vladikr/nova_drafts,Stavitsky/nova,cloudbase/nova,shootstar/novatest,adelina-t/nova,eharney/nova,jeffrey4l/nova,zaina/nova,belmiromoreira/nova,Juniper/nova,badock/nova,double12gzh/nova,tealover/nova,sacharya/nova,Stavitsky/nova,tealover/nova,alaski/nova,TieWei/nova,cyx1231st/nova,JioCloud/nova_test_latest,nikesh-mahalka/nova,CEG-FYP-OpenStack/scheduler,vmturbo/nova,LoHChina/nova,akash1808/nova_test_latest,rajalokan/nova,qwefi/nova,rajalokan/nova,plumgrid/plumgrid-nova,Yuriy-Leonov/nova,klmitch/nova,yatinkumbhare/openstack-nova,plumgrid/plumgrid-nova,cernops/nova,tudorvio/nova,ruslanloman/nova,mikalstill/nova,cyx1231st/nova,TieWei/nova,MountainWei/nova,zzicewind/nova,tangfeixiong/nova,mahak/nova,redhat-openstack/nova,CCI-MOC/nova,luogangyi/bcec-nova,bgxavier/nova,mahak/nova,akash1808/nova,affo/nova,CiscoSystems/nova,spring-week-topos/nova-week,Francis-Liu/animated-broccoli,cloudbau/nova,leilihh/nova,alvarolopez/nova,angdraug/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,felixma/nova,akash1808/nova_test_latest,zaina/nova,JioCloud/nova_test_latest,joker946/nova,watonyweng/nova,eayunstack/nova,apporc/nova,ewindisch/nova,tianweizhang/nova,saleemjaveds/https-github.com-openstack-nova,rajalokan/nova,OpenAcademy-OpenStack/nova-scheduler,watonyweng/nova,vmturbo/nova,bgxavier/nova,openstack/nova,shail2810/nova,zhimin711/nova,tudorvio/nova,berrange/nova,JianyuWang/nova,leilihh/novaha,rrader/nova-docker-plugin,apporc/nova,jianghuaw/nova,whitepages/nova,cernops/nova,sebrandon1/nova,CiscoSystems/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,iuliat/nova,sacharya/nova,shahar-stratoscale/nova,vmturbo/nova