Ensure that exception raised in neutron are handled correctly
Ensure that exception raised in neutron are handled correctly

We are now logging exceptions so we need to use save_and_reraise.

The patch set has also added log messages for exceptions that were
raised. This will be very helpful for debugging and troubleshooting.
This is done in the following cases:
 - unable to access a port when validating networks
 - unable to find a requested floating ip

Change-Id: I946126c2fb5aa229f917f8cb36ecb23aab528e14

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