listing the hosts for migration for instance with tag
Added marvin test for this issue.
Steps
1. Create a Compute service offering with the tag.
2. Create a Guest VM with the compute service offering
created above.
3. find hosts to migrate the vm crated above
Validations
1. Ensure that the offering is created with the
tag.The listServiceOffering API should list show tag
2. findHostsForMigration cmd should list both suitable
and not-suitable hosts
