ASGARD-629 - Security group should display dependencies

When a user tries to clean up a security group they need to know what instances, launch configs, and ELBs are holding references to the security group.

Also now showing VPC field on security group list, because sometimes we hit limits on the number of security groups we can have in one VPC, so we need to be able to filter the list on VPC.

Also fixed a minor bug I introduced while merging the Grails 2.2.4 upgrade changes.