Updated REST and SOAP API's to support External Authentication.

- Added a :require_user option to User.authenticate
- Added :timeout option to MiqTask.wait_for_taskid
- Updated REST API to pass HTTP Env and option to User.authenticate
- Updated Appliance Console to extend the Apache External configuration
to be REST and SOAP API aware.
- Properly unconfiguring HTTPD application from appliance console.
- Added REST API and SOAP :authentication_timeout config, both
default to 30 seconds
That's an awesome idea @chessbyte :+1: 

Similar suggestions for the hacky looking: 
`update_status(task_id, STATE_FINISHED, STATUS_TIMEOUT, "Timed out stalled task.")`

I thought something like this reads better:
`task.timeout("Timed out stalled task.")`