config groups UI: Added config-groups CRUD functions, locators and tests

Fixes some bugs related to config_groups tests

config groups UI: remove the unused import
Merge pull request #1156 from kbidarkar/config-groups

config groups UI: Added config-groups CRUD functions, locators and tests
Updated hostgroup test with Factory and added few -ve tests
Merge pull request #1170 from sghai/hostgroup

Updated hostgroup test with  Factory
Updated gpgkey tests with Factory and using api's for dependent entities
updated test_key_associate_20 test with api's

Updated create/delete/update tests with factory

Updated create/delete/update tests with factory

moved session statement after api calls and collapse tests
Merge pull request #1161 from sghai/gpgkey

Convered GPGKey tests to use Factory and APIs for dependent entities
Make decorator `skip_if_bug_open` more flexible

Make it possible to use decorator `skip_if_bug_open` on either test methods or
test cases. As part of this effort, move some business logic from
`skip_if_bug_open` to a helper function, and expand the set of tests in
`test_decorators.py` to exercise this new helper function.

Fix one usage of `skip_if_bug_open`, now that the decorator can be used on
TestCase classes in addition to just test methods.