Added test for removehostcollection for activationkey

Please review it
thanks
In this case, I think it is best to not provide an error message. If the test fails, the user will receive an error message stating "Names don't match". On the other hand, this assertion:

```python
self.assertEqual(new_host_col['name'], test_data['host-col'])
```

Produces an error message like `'OldName' != 'NewName'`. I think the latter error message will be much more helpful to someone debugging this error.

That said, this complaint applies to nearly all of the CLI test method assertions (that I've seen), so if we decide to change how error messages are written, that may best be done in a separate PR. @tkolhar, no need for you to take action here, but just think about what I've written. Perhaps @elyezer, @alda519 or @omaciel have thoughts on the subject?