added blockIssuance type

core/types/issuance.go

@@ -0,0 +1,20 @@
+package types
+
+import (
+	"encoding/json"
+	"math/big"
+)
+
+type BlockIssuance struct {
+	BlockReward *big.Int `json:"blockReward"`
+	UncleReward *big.Int `json:"uncleReward"`
+	Issuance    *big.Int `json:"issuance"`
+	TotalIssued *big.Int `json:"totalIssued"`
+	TotalBurnt  *big.Int `json:"totalBurnt"`
+}
+
+func Encode(data []byte) (BlockIssuance, error) {
+	var issuance BlockIssuance
+	err := json.Unmarshal(data, &issuance)
+	return issuance, err
+}