## Issue Addressed
#3006
## Proposed Changes
This PR changes the default behaviour of lighthouse to ignore discovered IPs that are not globally routable. It adds a CLI flag, --enable-local-discovery to permit the non-global IPs in discovery.
NOTE: We should take care in merging this as I will break current set-ups that rely on local IP discovery. I made this the non-default behaviour because we dont really want to be wasting resources attempting to connect to non-routable addresses and we dont want to propagate these to others (on the chance we can connect to one of these local nodes), improving discoveries efficiency.