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