Goal: 

• As an API user, I need to know when something's wrong with my requests by getting clear error message so I can fix them.

Right now, no error messages are provided, one needs to message lzap@redhat.com or oezr@redhat.com 

Acceptance Criteria:

• When AMI cannot be accessed, the error message gets back to the user.
• Basic argument validation
• AWS API errors are relayed back