This commit moves the constants LndInternalLockID and DefaultLockDuration from the walletrpc package to the chanfunding package, moves DefaultReservationTimeout from lncfg to chanfunding, and also updates the lncli package with the new location.
This adds an itest for a failed funding flow by our peer.
Make the interceptable switch aware of htlc expiry and fail back htlcs in-time to prevent the counterparty from force-closing the channel.
