Domain UI: Fix for searching domains and the move to factory
Move function into module robottelo.api.utils

Function `status_code_error` is useful in numerious different tests. Promote it
from being a private helper function to a public function. Adjust other code to
deal with the change
Improve error logging code.
Add support for field default values and choices.

If a field specifies that it has a default value or offers some set of choices,
then its get_value() method should respect that. Make fields do so, and add
tests to ensure this is the case.
Set default StringField max_len to 80

Doing this is entirely for convencience. Many fields on a Foreman server can
only accept up to 255 1-byte characters, and 80 3-byte characters (a unicode
char is often this long) will always fit within a field this size.
Add four more sets of API tests

Add some API tests for the following URL families:

* activation_keys/
* content_views/
* domains/
* repositories/
Nuke ShortStringField
Allow _get_value to accept raw default values
Automatically append _id and _id to field names

Entities have OneToOneField and OneToManyField names in this format:

    organization = orm.OneToOneField('Organization', required=True)

However, the Foreman API expects the '_id' and '_ids' suffix to be appended to
these same fields:

    {'organization_id': 15}

Insert logic into class EntityFactoryMixin that transforms field names as
appropriate.

Remove method Factory._get_field_names. This method added complexity to the
behaviour of Factory, and that complexity is unneeded, as no client code
actually relied on that logic in any good way. To accomodate this change, remove
the 'fmt' argument from Factory.attributes, Factory.build and Factory.create.

Rename two more methods:

* Factory._get_path to Factory._factory_path
* Factory._get_values to Factory._factory_data

The Factory class is used as a mixin (via EntityFactoryMixin) in numerous,
numerous Entity classes. Renaming these two fields helps avoid any potential
name conflicts with child classes, and also reduces confusion when reading
through EntityFactoryMixin.
Update tests for module robottelo.factory

A recent commit significantly changed the behaviour of the code in module
robottelo.factory. Update relevant tests to accomodate those changes.
UI: Added the set & remove domain parameter under try block
Travis fix test_domain module
Merge pull request #1041 from kbidarkar/domain-tests

Domain UI: Fix for searching domains and the move to factory
Merge pull request #1009 from Ichimonji10/api-tests

Add more API tests (and other API-related changes)