Description of problem:
When creating or updating a host, it is possible to specify an owner_type. From the API docs:

> host[owner_type]
> optional , nil allowed
> Host's owner type
> Value: Must be one of: User, Usergroup.

The "owner_type" attribute is set to "User" when creating a host, even if one provides a value of "Usergroup".

Version-Release number of selected component (if applicable):
Tested against Satellite-6.1.0-RHEL-6-20150317.0 and Satellite-6.1.0-RHEL-7-20150317.0.

How reproducible:
Always.

Steps to Reproduce:
1. Create a host. Specify an owner_type of "Usergroup".
2. Read back information about the just-created host. Examine the owner_type attribute.

Actual results:
A host is created with an owner type of "User".

Expected results:
A host is created with an owner type of "Usergroup".

Additional info: