Added Douglas and Einstan

ethutil/common.go

@@ -7,6 +7,8 @@ import (
 
 // The different number of units
 var (
+	Douglas  = BigPow(10, 42)
+	Einstein = BigPow(10, 21)
 	Ether    = BigPow(10, 18)
 	Finney   = BigPow(10, 15)
 	Szabo    = BigPow(10, 12)
@@ -21,6 +23,10 @@ var (
 // Returns a string representing a human readable format
 func CurrencyToString(num *big.Int) string {
 	switch {
+	case num.Cmp(Douglas) >= 0:
+		return fmt.Sprintf("%v Douglas", new(big.Int).Div(num, Douglas))
+	case num.Cmp(Einstein) >= 0:
+		return fmt.Sprintf("%v Einstein", new(big.Int).Div(num, Einstein))
 	case num.Cmp(Ether) >= 0:
 		return fmt.Sprintf("%v Ether", new(big.Int).Div(num, Ether))
 	case num.Cmp(Finney) >= 0: