Mistral Worker CLI

We need a Command Line Interface to be able to start a worker process that would connect to Mistral and poll for available actions. The suggestion is to have a configuration file containing details of how a worker process should connect to Mistral and handle incoming actions:
- Mistral service connection string
- "Action name"/"Command" key-value pairs for defining how to process certain actions where "Command" may be a script, binary or other instruction from a predefined list