1) Added API frameworks for the feature. New commands:
* CreateVPCCmd
* ListVPCsCmd
* DeleteVPCCmd
* UpdateVPCCmd
* CreateVPCOfferingCmd
* UpdateVPCOfferingCmd
* DeleteVPCOfferingCmd
* ListVPCOfferingsCmd
2) New db tables:
* `cloud`.`vpc`
* `cloud`.`vpc_offerings`
* `cloud`.`vpc_offering_service_map`
and corresponding VO/Dao objects.
Added vpc_id field to `cloud.`networks` table - not null when network belongs to VPC
3) New Manager and Service interfaces- VpcManager/VpcService
4) Automatically create new VpcOffering (if doesn't exist) on system start
5) New Action events:
* VPC.CREATE
* VPC.UPDATE
* VPC.DELETE
* VPC.OFFERING.CREATE
* VPC.OFFERING.UPDATE
* VPC.OFFERING.DELETE
TODO:
- Still leaving the provider columns in data_center schema as-is for CloudKit and BareMetal
- ExternalNetworkDeviceMgrImpl still needs to fix the dataCenter.setProviders calls and externalNetworkApplicance usage checks to see if zone has external networking.
* moved all services to the separate table, map them to the network_offering+provider.
* added state/securityGroupEnabled properties for the networkOffering
* added ability to list by state/securityGroupEnabled in listNetworkOfferings api command
2) New service: SourceNat