Persistance (#53)

* added publish TX for backwards compat.

* lowered the prototick for faster block syncing

* print useragent on startup

* added createMultiRedeemScript for genesis block generation.

* building genesis block from scratch.

* implemented merkle tree.

* starting blockhain with generated genesis hash

* Fixed bug in unspent coin state.

* fixed broken tests after genesis block.

* removed log line.

* bumped version -> 0.34.0

pkg/core/helper_test.go

@@ -31,11 +31,9 @@ func newBlock(index uint32, txs ...*transaction.Transaction) *Block {
 		},
 		Transactions: txs,
 	}
-	hash, err := b.createHash()
-	if err != nil {
-		panic(err)
-	}
-	b.hash = hash
+
+	b.createHash()
+
 	return b
 }