Add ability to populate missing blocks

* The command populates up to the highest known block number
 * The anticipated use case is that the listener will be running
   in parallel to the populateBlocks command
    * This will mean that the listener is responsible for picking up
      new blocks, and the populateBlocks command is reposible for
      historical blocks
 * Reformat SQL statements

integration_test/geth_blockchain_test.go

@@ -14,11 +14,12 @@ var _ = Describe("Reading from the Geth blockchain", func() {
 
 	var listener blockchain_listener.BlockchainListener
 	var observer *fakes.BlockchainObserver
+	var blockchain *geth.GethBlockchain
 
 	BeforeEach(func() {
 		observer = fakes.NewFakeBlockchainObserver()
 		cfg := config.NewConfig("private")
-		blockchain := geth.NewGethBlockchain(cfg.Client.IPCPath)
+		blockchain = geth.NewGethBlockchain(cfg.Client.IPCPath)
 		observers := []core.BlockchainObserver{observer}
 		listener = blockchain_listener.NewBlockchainListener(blockchain, observers)
 	})
@@ -43,4 +44,14 @@ var _ = Describe("Reading from the Geth blockchain", func() {
 		close(done)
 	}, 10)
 
+	It("retrieves the genesis block and first block", func(done Done) {
+		genesisBlock := blockchain.GetBlockByNumber(int64(0))
+		firstBlock := blockchain.GetBlockByNumber(int64(1))
+
+		Expect(genesisBlock.Number).To(Equal(int64(0)))
+		Expect(firstBlock.Number).To(Equal(int64(1)))
+
+		close(done)
+	}, 10)
+
 })