Don't explode if image.extra doesn't contain vm_image attribute.
Don't explode if image.extra doesn't contain vm_image attribute.

iPlantCollaborativeOpenSource/libcloud,watermelo/libcloud,aviweit/libcloud,thesquelched/libcloud,jimbobhickville/libcloud,DimensionDataCBUSydney/libcloud,sahildua2305/libcloud,Verizon/libcloud,cryptickp/libcloud,supertom/libcloud,Scalr/libcloud,atsaki/libcloud,briancurtin/libcloud,wido/libcloud,jerryblakley/libcloud,samuelchong/libcloud,wrigri/libcloud,ByteInternet/libcloud,marcinzaremba/libcloud,thesquelched/libcloud,sahildua2305/libcloud,briancurtin/libcloud,NexusIS/libcloud,schaubl/libcloud,mtekel/libcloud,DimensionDataCBUSydney/libcloud,pquentin/libcloud,Kami/libcloud,aleGpereira/libcloud,JamesGuthrie/libcloud,Cloud-Elasticity-Services/as-libcloud,MrBasset/libcloud,mbrukman/libcloud,watermelo/libcloud,marcinzaremba/libcloud,mistio/libcloud,wido/libcloud,sfriesel/libcloud,jerryblakley/libcloud,Itxaka/libcloud,andrewsomething/libcloud,MrBasset/libcloud,ZuluPro/libcloud,andrewsomething/libcloud,niteoweb/libcloud,sergiorua/libcloud,niteoweb/libcloud,apache/libcloud,curoverse/libcloud,mgogoulos/libcloud,wrigri/libcloud,Itxaka/libcloud,DimensionDataCBUSydney/libcloud,wuyuewen/libcloud,smaffulli/libcloud,mbrukman/libcloud,samuelchong/libcloud,cloudControl/libcloud,atsaki/libcloud,mistio/libcloud,kater169/libcloud,cryptickp/libcloud,carletes/libcloud,niteoweb/libcloud,ZuluPro/libcloud,t-tran/libcloud,aviweit/libcloud,Kami/libcloud,wrigri/libcloud,schaubl/libcloud,lochiiconnectivity/libcloud,samuelchong/libcloud,lochiiconnectivity/libcloud,wido/libcloud,sfriesel/libcloud,erjohnso/libcloud,cryptickp/libcloud,andrewsomething/libcloud,Cloud-Elasticity-Services/as-libcloud,jimbobhickville/libcloud,StackPointCloud/libcloud,mtekel/libcloud,sahildua2305/libcloud,curoverse/libcloud,mistio/libcloud,cloudControl/libcloud,mathspace/libcloud,schaubl/libcloud,dcorbacho/libcloud,techhat/libcloud,illfelder/libcloud,ByteInternet/libcloud,SecurityCompass/libcloud,MrBasset/libcloud,pquentin/libcloud,aleGpereira/libcloud,jerryblakley/libcloud,apache/libcloud,Scalr/libcloud,pantheon-systems/libcloud,NexusIS/libcloud,StackPointCloud/libcloud,kater169/libcloud,sergiorua/libcloud,vongazman/libcloud,vongazman/libcloud,Verizon/libcloud,supertom/libcloud,Verizon/libcloud,aviweit/libcloud,techhat/libcloud,JamesGuthrie/libcloud,kater169/libcloud,Scalr/libcloud,Cloud-Elasticity-Services/as-libcloud,dcorbacho/libcloud,NexusIS/libcloud,illfelder/libcloud,mgogoulos/libcloud,briancurtin/libcloud,ByteInternet/libcloud,atsaki/libcloud,t-tran/libcloud,Kami/libcloud,cloudControl/libcloud,t-tran/libcloud,lochiiconnectivity/libcloud,StackPointCloud/libcloud,carletes/libcloud,jimbobhickville/libcloud,SecurityCompass/libcloud,wuyuewen/libcloud,sergiorua/libcloud,erjohnso/libcloud,thesquelched/libcloud,SecurityCompass/libcloud,marcinzaremba/libcloud,mgogoulos/libcloud,mtekel/libcloud,illfelder/libcloud,smaffulli/libcloud,pquentin/libcloud,ZuluPro/libcloud,mbrukman/libcloud,wuyuewen/libcloud,curoverse/libcloud,mathspace/libcloud,vongazman/libcloud,JamesGuthrie/libcloud,techhat/libcloud,aleGpereira/libcloud,supertom/libcloud,sfriesel/libcloud,iPlantCollaborativeOpenSource/libcloud,pantheon-systems/libcloud,iPlantCollaborativeOpenSource/libcloud,erjohnso/libcloud,smaffulli/libcloud,pantheon-systems/libcloud,carletes/libcloud,Itxaka/libcloud,watermelo/libcloud,dcorbacho/libcloud,mathspace/libcloud,apache/libcloud