fixes melange ipam lib
fixes melange ipam lib

Melange can have multiple ip_blocks assigned to a network. However
the ipam lib assumes that each block is its own L2 network and assigns
ips from each ip_block for every instance.

From internal bug.

Change-Id: I72699f178cfeb214b2911200a7e9ed9b255252f1

phenoxim/nova,dims/nova,fnordahl/nova,sridevikoushik31/nova,yosshy/nova,cloudbau/nova,Francis-Liu/animated-broccoli,CloudServer/nova,rajalokan/nova,hanlind/nova,redhat-openstack/nova,virtualopensystems/nova,affo/nova,Yuriy-Leonov/nova,eharney/nova,Metaswitch/calico-nova,nikesh-mahalka/nova,barnsnake351/nova,MountainWei/nova,devendermishrajio/nova_test_latest,thomasem/nova,varunarya10/nova_test_latest,mgagne/nova,rrader/nova-docker-plugin,devendermishrajio/nova_test_latest,noironetworks/nova,tianweizhang/nova,edulramirez/nova,citrix-openstack-build/nova,psiwczak/openstack,isyippee/nova,jianghuaw/nova,devoid/nova,alvarolopez/nova,mandeepdhami/nova,maoy/zknova,joker946/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,bgxavier/nova,TwinkleChawla/nova,DirectXMan12/nova-hacking,usc-isi/extra-specs,j-carpentier/nova,LoHChina/nova,vmturbo/nova,JianyuWang/nova,bgxavier/nova,houshengbo/nova_vmware_compute_driver,gspilio/nova,belmiromoreira/nova,jianghuaw/nova,iuliat/nova,viggates/nova,JioCloud/nova_test_latest,SUSE-Cloud/nova,usc-isi/extra-specs,joker946/nova,orbitfp7/nova,shail2810/nova,JioCloud/nova,openstack/nova,paulmathews/nova,cernops/nova,alvarolopez/nova,cloudbase/nova-virtualbox,eayunstack/nova,takeshineshiro/nova,redhat-openstack/nova,russellb/nova,Tehsmash/nova,berrange/nova,Metaswitch/calico-nova,scripnichenko/nova,plumgrid/plumgrid-nova,tudorvio/nova,vmturbo/nova,dstroppa/openstack-smartos-nova-grizzly,yatinkumbhare/openstack-nova,takeshineshiro/nova,rahulunair/nova,BeyondTheClouds/nova,aristanetworks/arista-ovs-nova,isyippee/nova,eayunstack/nova,affo/nova,zaina/nova,badock/nova,luogangyi/bcec-nova,klmitch/nova,eneabio/nova,houshengbo/nova_vmware_compute_driver,Juniper/nova,cloudbase/nova-virtualbox,blueboxgroup/nova,NeCTAR-RC/nova,akash1808/nova,usc-isi/nova,leilihh/novaha,Francis-Liu/animated-broccoli,raildo/nova,sebrandon1/nova,russellb/nova,ntt-sic/nova,badock/nova,phenoxim/nova,MountainWei/nova,ntt-sic/nova,raildo/nova,rajalokan/nova,zhimin711/nova,aristanetworks/arista-ovs-nova,Triv90/Nova,Triv90/Nova,devoid/nova,josephsuh/extra-specs,felixma/nova,klmitch/nova,fajoy/nova,eneabio/nova,DirectXMan12/nova-hacking,gooddata/openstack-nova,cernops/nova,akash1808/nova,tianweizhang/nova,mikalstill/nova,sacharya/nova,usc-isi/extra-specs,openstack/nova,angdraug/nova,JioCloud/nova_test_latest,eharney/nova,whitepages/nova,fnordahl/nova,maheshp/novatest,apporc/nova,openstack/nova,jeffrey4l/nova,CEG-FYP-OpenStack/scheduler,rrader/nova-docker-plugin,sridevikoushik31/nova,cyx1231st/nova,bigswitch/nova,leilihh/nova,sileht/deb-openstack-nova,rahulunair/nova,shahar-stratoscale/nova,tudorvio/nova,Yuriy-Leonov/nova,alaski/nova,maelnor/nova,scripnichenko/nova,petrutlucian94/nova_dev,fajoy/nova,devendermishrajio/nova,maoy/zknova,mahak/nova,paulmathews/nova,NewpTone/stacklab-nova,CCI-MOC/nova,shail2810/nova,rahulunair/nova,ted-gould/nova,usc-isi/nova,tealover/nova,Brocade-OpenSource/OpenStack-DNRM-Nova,gspilio/nova,yatinkumbhare/openstack-nova,OpenAcademy-OpenStack/nova-scheduler,nikesh-mahalka/nova,hanlind/nova,gooddata/openstack-nova,dstroppa/openstack-smartos-nova-grizzly,apporc/nova,Triv90/Nova,zhimin711/nova,blueboxgroup/nova,vladikr/nova_drafts,sridevikoushik31/openstack,savi-dev/nova,BeyondTheClouds/nova,CloudServer/nova,viggates/nova,mmnelemane/nova,qwefi/nova,jianghuaw/nova,jianghuaw/nova,CCI-MOC/nova,gooddata/openstack-nova,virtualopensystems/nova,orbitfp7/nova,tangfeixiong/nova,DirectXMan12/nova-hacking,TieWei/nova,paulmathews/nova,qwefi/nova,ewindisch/nova,ruslanloman/nova,saleemjaveds/https-github.com-openstack-nova,whitepages/nova,vmturbo/nova,JioCloud/nova,gooddata/openstack-nova,rajalokan/nova,double12gzh/nova,zzicewind/nova,kimjaejoong/nova,psiwczak/openstack,Yusuke1987/openstack_template,shahar-stratoscale/nova,CEG-FYP-OpenStack/scheduler,tealover/nova,dstroppa/openstack-smartos-nova-grizzly,mahak/nova,tanglei528/nova,imsplitbit/nova,NoBodyCam/TftpPxeBootBareMetal,cloudbase/nova,yrobla/nova,eneabio/nova,citrix-openstack-build/nova,projectcalico/calico-nova,Stavitsky/nova,houshengbo/nova_vmware_compute_driver,yrobla/nova,sileht/deb-openstack-nova,rajalokan/nova,mahak/nova,rickerc/nova_audit,vmturbo/nova,fajoy/nova,shootstar/novatest,felixma/nova,alaski/nova,eonpatapon/nova,savi-dev/nova,TwinkleChawla/nova,yrobla/nova,mikalstill/nova,barnsnake351/nova,sacharya/nova,savi-dev/nova,sebrandon1/nova,klmitch/nova,tanglei528/nova,cernops/nova,ted-gould/nova,maheshp/novatest,silenceli/nova,ruslanloman/nova,angdraug/nova,thomasem/nova,edulramirez/nova,zzicewind/nova,Yusuke1987/openstack_template,NeCTAR-RC/nova,noironetworks/nova,cloudbase/nova,projectcalico/calico-nova,mmnelemane/nova,klmitch/nova,double12gzh/nova,NewpTone/stacklab-nova,OpenAcademy-OpenStack/nova-scheduler,psiwczak/openstack,petrutlucian94/nova,russellb/nova,SUSE-Cloud/nova,cloudbase/nova,varunarya10/nova_test_latest,kimjaejoong/nova,dawnpower/nova,sileht/deb-openstack-nova,maelnor/nova,dims/nova,NewpTone/stacklab-nova,aristanetworks/arista-ovs-nova,tangfeixiong/nova,devendermishrajio/nova,mandeepdhami/nova,jeffrey4l/nova,mgagne/nova,yosshy/nova,usc-isi/nova,watonyweng/nova,cyx1231st/nova,belmiromoreira/nova,plumgrid/plumgrid-nova,sridevikoushik31/openstack,petrutlucian94/nova_dev,sridevikoushik31/nova,leilihh/nova,dawnpower/nova,adelina-t/nova,akash1808/nova_test_latest,mikalstill/nova,CiscoSystems/nova,imsplitbit/nova,alexandrucoman/vbox-nova-driver,rickerc/nova_audit,maheshp/novatest,ewindisch/nova,sebrandon1/nova,leilihh/novaha,sridevikoushik31/openstack,alexandrucoman/vbox-nova-driver,spring-week-topos/nova-week,Stavitsky/nova,Juniper/nova,vladikr/nova_drafts,spring-week-topos/nova-week,josephsuh/extra-specs,bigswitch/nova,iuliat/nova,akash1808/nova_test_latest,Juniper/nova,zaina/nova,bclau/nova,LoHChina/nova,JianyuWang/nova,silenceli/nova,cloudbau/nova,josephsuh/extra-specs,petrutlucian94/nova,maoy/zknova,watonyweng/nova,berrange/nova,luogangyi/bcec-nova,bclau/nova,sridevikoushik31/nova,Tehsmash/nova,gspilio/nova,adelina-t/nova,eonpatapon/nova,shootstar/novatest,BeyondTheClouds/nova,saleemjaveds/https-github.com-openstack-nova,hanlind/nova,TieWei/nova,Juniper/nova,NoBodyCam/TftpPxeBootBareMetal,NoBodyCam/TftpPxeBootBareMetal,j-carpentier/nova,CiscoSystems/nova