updated template tests with factory
removed create_template fn
small update in ddt test
seven negative tests
Subnet UI: Added boundary tests for subnet, converted to factory and associate domain to subnet testcase
Updated CLI factory for HostGroup command.

Looks like the 'create' method for the 'hostgroup' command has been
updated to include more options.

```bash
Usage:
    hammer hostgroup create [OPTIONS]

Options:
    --architecture ARCHITECTURE_NAME Architecture name
    --architecture-id ARCHITECTURE_ID
    --domain DOMAIN_NAME          Domain name
    --domain-id DOMAIN_ID         May be numerical id or domain name
    --environment ENVIRONMENT_NAME Environment name
    --environment-id ENVIRONMENT_ID
    --medium MEDIUM_NAME          Medium name
    --medium-id MEDIUM_ID
    --name NAME
    --operatingsystem-id OPERATINGSYSTEM_ID
    --parent-id PARENT_ID
    --ptable PTABLE_NAME          Partition table name
    --ptable-id PTABLE_ID
    --puppet-ca-proxy-id PUPPET_CA_PROXY_ID
    --puppet-proxy-id PUPPET_PROXY_ID
    --puppetclass-ids PUPPETCLASS_IDS Comma separated list of values.
    --realm REALM_NAME            Name to search by
    --realm-id REALM_ID           May be numerical id or realm name
    --subnet SUBNET_NAME          Subnet name
    --subnet-id SUBNET_ID
    -h, --help                    print help
```
Added more methods to CLI smoke test suite.

As per feedback I received via email, I have updated the existing CLI
smoke test to include the creation of ``Foreman`` artifacts. A further
tweak will be added to make sure that all artifacts are properly
associated with each other in an upcoming pull request.
Fixing help text to avoid markdown conflict.
One more tweak to resolve formatting issue.
Merge pull request #1063 from omaciel/more-smoke

More smoke
subnet UI: Added docstrings to configure_subnet & fix the FILTER constants dictionary
Add headless UI target to Makefile

This target allows run the UI tests using xvfb-run which allows run the
UI tests without having browser windows popping up and also run on
machines with no display
Merge pull request #1065 from elyezer/headless-ui-target

Add headless UI target to Makefile
Merge pull request #1058 from sghai/template

Boundary tests for templates
Merge pull request #1057 from kbidarkar/boundary-subnet-tests

Subnet UI: Added boundary tests for subnet, converted to factory...
Improve API tests that make POST requests

There are API tests that issue HTTP POST requests and check the status code
returned by those HTTP requests. However, there are not tests which check
whether the just-created entities actually exist, nor whether their attributes
are correct. Add tests of this kind.