CLI to spawn Workers

The scripts used to spawn workers consist of a lot of repetitive code, it would be really useful to have a CLI instead.
The CLI could have options like:

code-executor spawn-worker --name myExecutor -n 10 --redis "redis://127.0.0.1:6379"

This spawns 10 workers on the server with the redis instance for managing the queue located at `redis://127.0.0.1:6379

Related Issues : #17 #25

The Question or Assignment model needs to be updated with a new field base_code.
Used by Moss for ignoring student submissions which match with it.

Additional Context
Different Templates can be provided to professors for easier usage. For e.g
A C++ base code may contain following content.

#include <iostream>
#include <vector>
#include <strin