multi: rename FeePreference to FeeEstimateInfo

Results from running,
```
gofmt -d -w -r 'FeePreference -> FeeEstimateInfo' .
```

contractcourt/anchor_resolver.go

@@ -115,7 +115,7 @@ func (c *anchorResolver) Resolve() (ContractResolver, error) {
 	resultChan, err := c.Sweeper.SweepInput(
 		&anchorInput,
 		sweep.Params{
-			Fee: sweep.FeePreference{
+			Fee: sweep.FeeEstimateInfo{
 				FeeRate: relayFeeRate,
 			},
 		},

contractcourt/channel_arbitrator.go

@@ -1359,7 +1359,7 @@ func (c *ChannelArbitrator) sweepAnchors(anchors *lnwallet.AnchorResolutions,
 		_, err = c.cfg.Sweeper.SweepInput(
 			&anchorInput,
 			sweep.Params{
-				Fee: sweep.FeePreference{
+				Fee: sweep.FeeEstimateInfo{
 					ConfTarget: deadline,
 				},
 				Force:          force,

contractcourt/commit_sweep_resolver.go

@@ -351,7 +351,7 @@ func (c *commitSweepResolver) Resolve() (ContractResolver, error) {
 	// sweeper.
 	c.log.Infof("sweeping commit output")
 
-	feePref := sweep.FeePreference{ConfTarget: commitOutputConfTarget}
+	feePref := sweep.FeeEstimateInfo{ConfTarget: commitOutputConfTarget}
 	resultChan, err := c.Sweeper.SweepInput(inp, sweep.Params{Fee: feePref})
 	if err != nil {
 		c.log.Errorf("unable to sweep input: %v", err)

contractcourt/commit_sweep_resolver_test.go

@@ -141,7 +141,7 @@ func (s *mockSweeper) SweepInput(input input.Input, params sweep.Params) (
 }
 
 func (s *mockSweeper) CreateSweepTx(inputs []input.Input,
-	feePref sweep.FeePreference) (*wire.MsgTx, error) {
+	feePref sweep.FeeEstimateInfo) (*wire.MsgTx, error) {
 
 	// We will wait for the test to supply the sweep tx to return.
 	sweepTx := <-s.createSweepTxChan

contractcourt/htlc_success_resolver.go

@@ -263,7 +263,7 @@ func (h *htlcSuccessResolver) broadcastReSignedSuccessTx() (
 		_, err := h.Sweeper.SweepInput(
 			&secondLevelInput,
 			sweep.Params{
-				Fee: sweep.FeePreference{
+				Fee: sweep.FeeEstimateInfo{
 					ConfTarget: secondLevelConfTarget,
 				},
 			},
@@ -375,7 +375,7 @@ func (h *htlcSuccessResolver) broadcastReSignedSuccessTx() (
 	_, err = h.Sweeper.SweepInput(
 		inp,
 		sweep.Params{
-			Fee: sweep.FeePreference{
+			Fee: sweep.FeeEstimateInfo{
 				ConfTarget: sweepConfTarget,
 			},
 		},
@@ -436,7 +436,7 @@ func (h *htlcSuccessResolver) resolveRemoteCommitOutput() (
 		var err error
 		h.sweepTx, err = h.Sweeper.CreateSweepTx(
 			[]input.Input{inp},
-			sweep.FeePreference{
+			sweep.FeeEstimateInfo{
 				ConfTarget: sweepConfTarget,
 			},
 		)

contractcourt/htlc_timeout_resolver.go

@@ -486,7 +486,7 @@ func (h *htlcTimeoutResolver) sweepSecondLevelTx() error {
 	_, err := h.Sweeper.SweepInput(
 		inp,
 		sweep.Params{
-			Fee: sweep.FeePreference{
+			Fee: sweep.FeeEstimateInfo{
 				ConfTarget: secondLevelConfTarget,
 			},
 			Force: true,
@@ -702,7 +702,7 @@ func (h *htlcTimeoutResolver) handleCommitSpend(
 		_, err = h.Sweeper.SweepInput(
 			inp,
 			sweep.Params{
-				Fee: sweep.FeePreference{
+				Fee: sweep.FeeEstimateInfo{
 					ConfTarget: sweepConfTarget,
 				},
 			},

contractcourt/interfaces.go

@@ -54,7 +54,7 @@ type UtxoSweeper interface {
 	// that spends from them. This method also makes an accurate fee
 	// estimate before generating the required witnesses.
 	CreateSweepTx(inputs []input.Input,
-		feePref sweep.FeePreference) (*wire.MsgTx, error)
+		feePref sweep.FeeEstimateInfo) (*wire.MsgTx, error)
 
 	// RelayFeePerKW returns the minimum fee rate required for transactions
 	// to be relayed.

contractcourt/utxonursery.go

@@ -823,7 +823,7 @@ func (u *UtxoNursery) sweepMatureOutputs(classHeight uint32,
 	utxnLog.Infof("Sweeping %v CSV-delayed outputs with sweep tx for "+
 		"height %v", len(kgtnOutputs), classHeight)
 
-	feePref := sweep.FeePreference{ConfTarget: kgtnOutputConfTarget}
+	feePref := sweep.FeeEstimateInfo{ConfTarget: kgtnOutputConfTarget}
 	for _, output := range kgtnOutputs {
 		// Create local copy to prevent pointer to loop variable to be
 		// passed in with disastrous consequences.