Integrate Ansible core tower modules content into AWX

This commit includes all the changes involved in
converting the old Ansible Tower modules from commits
in Ansible core into the AWX collection that replaces it.
Also includes work needed to integrate it into the
AWX processes like tests, docs, and the Makefile.

Apply changes from content_collector tool

Add integrated module tests
  operate via run_module fixture
  add makefile target for them

Add flake8 target and fix flake8 errors

Update README

Make consolidated target for testing modules

awx_modules/plugins/modules/tower_job_wait.py

@@ -82,7 +82,7 @@ status:
 '''
 
 
-from ansible.module_utils.ansible_tower import TowerModule, tower_auth_config, tower_check_mode
+from ..module_utils.ansible_tower import TowerModule, tower_auth_config, tower_check_mode
 from ansible.module_utils.six.moves import cStringIO as StringIO
 
 
@@ -125,7 +125,7 @@ def main():
         job_id = params.get('job_id')
         try:
             result = job.monitor(job_id, **params)
-        except exc.Timeout as excinfo:
+        except exc.Timeout:
             result = job.status(job_id)
             result['id'] = job_id
             json_output['msg'] = 'Timeout waiting for job to finish.'