lnwallet: the BreachRetribution struct is now aware of HTLC outputs
lnwallet: the BreachRetribution struct is now aware of HTLC outputs

This commit adds awareness of active HTLC outputs to the
BreachRetribution struct. Previously, in the case of a breach, the
struct was only populated with enough information to sweep the two
commitment outputs. With this commit, the struct now has enough
information to sweep _all_ outputs within the commitment transaction.

LightningNetwork/lnd,ddustin/lnd,AndrewSamokhvalov/lnd,aakselrod/lnd,LightningNetwork/lnd,aakselrod/lnd,AndrewSamokhvalov/lnd,ddustin/lnd