contractcourt/chain_arbitrator: mark commitment broadcasted before publish
contractcourt/chain_arbitrator: mark commitment broadcasted before publish

Before publishing the close tx to the network and commit to the
StateCommitmentBroadcasted state, we mark the commitment as broadcasted
and store it to the db. This ensures it will get re-published on startup
if we go down.

LightningNetwork/lnd,aakselrod/lnd,aakselrod/lnd,LightningNetwork/lnd