Creates database of related subreddits:
- A specified subreddit is inspected for related subreddits using description on page
- Related subreddits are then inspected for their related subs until the backlog is exhausted
- Related subreddits and backlog are stored in MongoDB throughout the process
- A progress script can be run with the crawler to report status
- Graphviz files can be generated the describe the mined data