Add tests for host-collection and content-host

Add tests for host-collection and content-host

Add tests for host-collection and content-host

Add tests for host-collection and content-host

Add tests for host-collection and content-host
replaced the name content_host to content_hosts in test_hostcollection
formatted the the code in host_collection.py
Merge pull request #1248 from tkolhar/test_cli

Added tests for host-collection content-host
Make Repository.read work correctly

Add `EntityReadMixin` to the `Repository` class. Override the `read` method,
allowing it to deal with the fact that issuing an HTTP GET to the API returns a
"product" hash containing an ID, but not a "product_id" integer as expected.

Test this change.

Update `EntityReadMixin` to deal with the fact that `OneToOneField`s and
`OneToManyField`s may contain either classes or strings naming classes.