misc: add ability to store the wallet in the remote DB

lnwallet/btcwallet/config.go

@@ -28,10 +28,6 @@ var (
 // Config is a struct which houses configuration parameters which modify the
 // instance of BtcWallet generated by the New() function.
 type Config struct {
-	// DataDir is the name of the directory where the wallet's persistent
-	// state should be stored.
-	DataDir string
-
 	// LogDir is the name of the directory which should be used to store
 	// generated log files.
 	LogDir string
@@ -76,14 +72,8 @@ type Config struct {
 	// normally when creating the BtcWallet.
 	Wallet *wallet.Wallet
 
-	// NoFreelistSync, if true, prevents the database from syncing its
-	// freelist to disk, resulting in improved performance at the expense of
-	// increased startup time.
-	NoFreelistSync bool
-
-	// DBTimeOut specifies the timeout value to use when opening the wallet
-	// database.
-	DBTimeOut time.Duration
+	// LoaderOptions holds functional wallet db loader options.
+	LoaderOptions []LoaderOption
 }
 
 // NetworkDir returns the directory name of a network directory to hold wallet