This commit hooks up the banman to the gossiper:
- peers that are banned and don't have a channel with us will get
disconnected until they are unbanned.
- peers that are banned and have a channel with us won't get
disconnected, but we will ignore their channel announcements until
they are no longer banned. Note that this only disables gossip of
announcements to us and still allows us to open channels to them.
Eugene Siegel
013452cff0