chainntnfs: TxConfNotifier struct to implement shared notifer logic.
chainntnfs: TxConfNotifier struct to implement shared notifer logic.

All implementations of the ChainNotifier interface support registering
notifications on transaction confirmations. This struct is intended to
be used internally by ChainNotifier implementations to handle much of
this logic.

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