Config File Support

[jasonrdsouza]

Add support for a config file (.sqsrd?) to make it easier to use the tool with common queues/ credentials. Likely YAML syntax? For example:

• alias for commonly redriven queues (source and destination)
• allow specifying profile and other CLI options so a given alias has all of the settings it needs to run simply by specifying the alias name
  • parallelism configuration, etc.