Get logs for a contract (#99)

* Add ability to fetch logs for a contract and a block

* Test contract related code against Infura, so can run on Travis

* Add godo task for getLogs

cmd/show_contract_summary/main.go

@@ -7,8 +7,6 @@ import (
 
 	"fmt"
 
-	"math/big"
-
 	"github.com/8thlight/vulcanizedb/cmd"
 	"github.com/8thlight/vulcanizedb/pkg/contract_summary"
 	"github.com/8thlight/vulcanizedb/pkg/geth"
@@ -22,7 +20,7 @@ func main() {
 	config := cmd.LoadConfig(*environment)
 	blockchain := geth.NewGethBlockchain(config.Client.IPCPath)
 	repository := cmd.LoadPostgres(config.Database, blockchain.Node())
-	blockNumber := requestedBlockNumber(_blockNumber)
+	blockNumber := cmd.RequestedBlockNumber(_blockNumber)
 
 	contractSummary, err := contract_summary.NewSummary(blockchain, repository, *contractHash, blockNumber)
 	if err != nil {
@@ -31,13 +29,3 @@ func main() {
 	output := contract_summary.GenerateConsoleOutput(contractSummary)
 	fmt.Println(output)
 }
-
-func requestedBlockNumber(blockNumber *int64) *big.Int {
-	var _blockNumber *big.Int
-	if *blockNumber == -1 {
-		_blockNumber = nil
-	} else {
-		_blockNumber = big.NewInt(*blockNumber)
-	}
-	return _blockNumber
-}