Support for local file list of IP ranges

[0xdade]

It's likely that we'll want to be able to also include blocks for various things that aren't just cloud providers. Things like security companies, or whatever else. Example list: https://gist.github.com/curi0usJack/971385e8334e189d93a6cb4671238b10

Add in a flag that uses a local file as the list of ranges. Probably in a simple format:

127.0.0.1/8, Some comment

or maybe a simple json format so that it doesn't require it's own parsing, but then adding things to the list is a heavier task.

{
    "range": "127.0.0.1/8",
    "comment": "Some comment"
}