Add total runtime to summary output
Add total runtime to summary output

This commit adds the total runtime in secs to the summary view from
subunit-trace.py

Change-Id: If56f2a048b3d1ab3d51425d5b3560e1f365a6c3a

yamt/tempest,FujitsuEnablingSoftwareTechnologyGmbH/tempest,flyingfish007/tempest,xbezdick/tempest,vedujoshi/tempest,tonyli71/tempest,hayderimran7/tempest,cisco-openstack/tempest,alinbalutoiu/tempest,pandeyop/tempest,Juniper/tempest,Lilywei123/tempest,dkalashnik/tempest,nunogt/tempest,alinbalutoiu/tempest,xbezdick/tempest,tudorvio/tempest,akash1808/tempest,redhat-cip/tempest,Juraci/tempest,pandeyop/tempest,izadorozhna/tempest,redhat-cip/tempest,afaheem88/tempest_neutron,yamt/tempest,izadorozhna/tempest,NexusIS/tempest,sebrandon1/tempest,Lilywei123/tempest,JioCloud/tempest,openstack/tempest,FujitsuEnablingSoftwareTechnologyGmbH/tempest,Mirantis/tempest,danielmellado/tempest,cloudbase/lis-tempest,Juraci/tempest,ebagdasa/tempest,Mirantis/tempest,hpcloud-mon/tempest,Tesora/tesora-tempest,openstack/tempest,neerja28/Tempest,eggmaster/tempest,NexusIS/tempest,rzarzynski/tempest,varunarya10/tempest,masayukig/tempest,pczerkas/tempest,zsoltdudas/lis-tempest,afaheem88/tempest,masayukig/tempest,jaspreetw/tempest,Vaidyanath/tempest,bigswitch/tempest,tudorvio/tempest,cisco-openstack/tempest,cloudbase/lis-tempest,flyingfish007/tempest,ebagdasa/tempest,hpcloud-mon/tempest,rzarzynski/tempest,Vaidyanath/tempest,tonyli71/tempest,rakeshmi/tempest,LIS/lis-tempest,Juniper/tempest,manasi24/jiocloud-tempest-qatempest,roopali8/tempest,akash1808/tempest,jamielennox/tempest,pczerkas/tempest,manasi24/tempest,jaspreetw/tempest,dkalashnik/tempest,zsoltdudas/lis-tempest,danielmellado/tempest,Tesora/tesora-tempest,hayderimran7/tempest,manasi24/jiocloud-tempest-qatempest,manasi24/tempest,afaheem88/tempest_neutron,eggmaster/tempest,roopali8/tempest,bigswitch/tempest,queria/my-tempest,varunarya10/tempest,JioCloud/tempest,CiscoSystems/tempest,queria/my-tempest,sebrandon1/tempest,afaheem88/tempest,LIS/lis-tempest,nunogt/tempest,rakeshmi/tempest,vedujoshi/tempest,jamielennox/tempest,neerja28/Tempest,CiscoSystems/tempest