Automate deletion of Infrastructure and cloud objects

Added test for deletion of infrastructure and cloud objects
Spoke with @psav and we came up with a solid compromise... lets add a block under the each provider (which is probably over kill but this is doing some implicit testing of ems_refresh) definition to specify what to remove and re-discover.  You can code it up for just a single provider today and we can add more later, start with vsphere5

something like the following
```
management_systems:
    vsphere55:
        remove_test:
            cluster:   xxx
            datastore:  xxx
            resource_pool:  xxx
            template:  xxx
            etc
```