Refactors VIF configuration logic
Refactors VIF configuration logic

There are too many if/else checks when we choose the right function to
conduct vif operations. We can do better by getattr on the nessesary
function obj. The vif type needs normalization to remove periods.

Change-Id: I6bb2af45d3e72bdc11470877fd2a993e9d0a4623

adelina-t/nova,ruslanloman/nova,raildo/nova,affo/nova,gooddata/openstack-nova,vmturbo/nova,Francis-Liu/animated-broccoli,Francis-Liu/animated-broccoli,Tehsmash/nova,devendermishrajio/nova,mandeepdhami/nova,tianweizhang/nova,akash1808/nova_test_latest,NeCTAR-RC/nova,ted-gould/nova,mgagne/nova,saleemjaveds/https-github.com-openstack-nova,devendermishrajio/nova_test_latest,yosshy/nova,shail2810/nova,varunarya10/nova_test_latest,cernops/nova,eonpatapon/nova,hanlind/nova,vmturbo/nova,blueboxgroup/nova,eonpatapon/nova,BeyondTheClouds/nova,openstack/nova,CEG-FYP-OpenStack/scheduler,bigswitch/nova,CEG-FYP-OpenStack/scheduler,projectcalico/calico-nova,sebrandon1/nova,kimjaejoong/nova,tudorvio/nova,jianghuaw/nova,felixma/nova,edulramirez/nova,MountainWei/nova,Juniper/nova,gooddata/openstack-nova,openstack/nova,petrutlucian94/nova,devendermishrajio/nova,apporc/nova,JioCloud/nova_test_latest,mmnelemane/nova,scripnichenko/nova,gooddata/openstack-nova,vladikr/nova_drafts,Juniper/nova,silenceli/nova,joker946/nova,mmnelemane/nova,cloudbase/nova-virtualbox,akash1808/nova_test_latest,fnordahl/nova,cyx1231st/nova,bgxavier/nova,berrange/nova,vmturbo/nova,adelina-t/nova,zhimin711/nova,j-carpentier/nova,yatinkumbhare/openstack-nova,hanlind/nova,tangfeixiong/nova,akash1808/nova,orbitfp7/nova,mikalstill/nova,edulramirez/nova,zaina/nova,CloudServer/nova,shail2810/nova,redhat-openstack/nova,rajalokan/nova,tianweizhang/nova,nikesh-mahalka/nova,rajalokan/nova,jianghuaw/nova,openstack/nova,silenceli/nova,klmitch/nova,virtualopensystems/nova,dawnpower/nova,jianghuaw/nova,phenoxim/nova,rahulunair/nova,iuliat/nova,whitepages/nova,dawnpower/nova,viggates/nova,mahak/nova,noironetworks/nova,klmitch/nova,felixma/nova,isyippee/nova,cloudbase/nova,takeshineshiro/nova,akash1808/nova,alexandrucoman/vbox-nova-driver,cloudbase/nova,zzicewind/nova,cloudbase/nova,cernops/nova,zhimin711/nova,joker946/nova,CCI-MOC/nova,maelnor/nova,takeshineshiro/nova,alvarolopez/nova,tangfeixiong/nova,barnsnake351/nova,berrange/nova,viggates/nova,CCI-MOC/nova,dims/nova,bigswitch/nova,iuliat/nova,orbitfp7/nova,jeffrey4l/nova,ruslanloman/nova,thomasem/nova,dims/nova,double12gzh/nova,MountainWei/nova,mahak/nova,hanlind/nova,noironetworks/nova,NeCTAR-RC/nova,belmiromoreira/nova,scripnichenko/nova,Stavitsky/nova,Metaswitch/calico-nova,kimjaejoong/nova,mikalstill/nova,mikalstill/nova,alaski/nova,raildo/nova,mgagne/nova,eayunstack/nova,jeffrey4l/nova,alexandrucoman/vbox-nova-driver,double12gzh/nova,BeyondTheClouds/nova,JioCloud/nova,isyippee/nova,barnsnake351/nova,LoHChina/nova,sebrandon1/nova,cloudbase/nova-virtualbox,tealover/nova,nikesh-mahalka/nova,fnordahl/nova,bgxavier/nova,gooddata/openstack-nova,mandeepdhami/nova,apporc/nova,angdraug/nova,cyx1231st/nova,thomasem/nova,phenoxim/nova,badock/nova,devendermishrajio/nova_test_latest,blueboxgroup/nova,petrutlucian94/nova,maelnor/nova,alaski/nova,sebrandon1/nova,whitepages/nova,vladikr/nova_drafts,CloudServer/nova,tealover/nova,klmitch/nova,yosshy/nova,angdraug/nova,cernops/nova,badock/nova,eayunstack/nova,JianyuWang/nova,mahak/nova,BeyondTheClouds/nova,jianghuaw/nova,virtualopensystems/nova,varunarya10/nova_test_latest,rahulunair/nova,Tehsmash/nova,Juniper/nova,ted-gould/nova,yatinkumbhare/openstack-nova,Yusuke1987/openstack_template,redhat-openstack/nova,zaina/nova,Juniper/nova,tudorvio/nova,JioCloud/nova,rajalokan/nova,rajalokan/nova,watonyweng/nova,watonyweng/nova,JioCloud/nova_test_latest,klmitch/nova,Metaswitch/calico-nova,belmiromoreira/nova,zzicewind/nova,vmturbo/nova,TwinkleChawla/nova,LoHChina/nova,alvarolopez/nova,JianyuWang/nova,Yusuke1987/openstack_template,projectcalico/calico-nova,rahulunair/nova,saleemjaveds/https-github.com-openstack-nova,affo/nova,j-carpentier/nova,Stavitsky/nova,TwinkleChawla/nova