Added generic big to 256 method. Implemented new iterator

ethtrie/slice.go

@@ -1,6 +1,9 @@
 package ethtrie
 
-import "math"
+import (
+	"bytes"
+	"math"
+)
 
 // Helper function for comparing slices
 func CompareIntSlice(a, b []int) bool {
@@ -16,7 +19,7 @@ func CompareIntSlice(a, b []int) bool {
 }
 
 // Returns the amount of nibbles that match each other from 0 ...
-func MatchingNibbleLength(a, b []int) int {
+func MatchingNibbleLength(a, b []byte) int {
 	var i, length = 0, int(math.Min(float64(len(a)), float64(len(b))))
 
 	for i < length {
@@ -28,3 +31,23 @@ func MatchingNibbleLength(a, b []int) int {
 
 	return i
 }
+
+func HasTerm(s []byte) bool {
+	return s[len(s)-1] == 16
+}
+
+func RemTerm(s []byte) []byte {
+	if HasTerm(s) {
+		return s[:len(s)-1]
+	}
+
+	return s
+}
+
+func BeginsWith(a, b []byte) bool {
+	if len(b) > len(a) {
+		return false
+	}
+
+	return bytes.Equal(a[:len(b)], b)
+}