Sync only missing blocks on cold import

= Add eth_node_fingerprint to block that can be imitated by both hot and cold imports
- Only sync missing blocks (blocks that are missing or don't share a fingerprint) on cold import
- Set block is_final status after import

pkg/crypto/parser_test.go

@@ -0,0 +1,19 @@
+package crypto_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/vulcanize/vulcanizedb/pkg/crypto"
+)
+
+var _ = Describe("Public key parser", func() {
+	It("parses public key from private key", func() {
+		privKey := "0000000000000000000000000000000000000000000000000000000000000001"
+		parser := crypto.EthPublicKeyParser{}
+
+		pubKey, err := parser.ParsePublicKey(privKey)
+
+		Expect(err).NotTo(HaveOccurred())
+		Expect(pubKey).To(Equal("79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8"))
+	})
+})