multi: rename key_send, key-send and key send to keysend

channeldb/invoices.go

@@ -220,7 +220,7 @@ type Invoice struct {
 	Memo []byte
 
 	// PaymentRequest is the encoded payment request for this invoice. For
-	// spontaneous (key send) payments, this field will be empty.
+	// spontaneous (keysend) payments, this field will be empty.
 	PaymentRequest []byte
 
 	// CreationDate is the exact time the invoice was created.