Add integration test

* Update Travis to run integration tests

scripts/setup

@@ -0,0 +1,6 @@
+#!/bin/bash
+echo "Deleting test blockchain"
+rm -rf test_data_dir
+echo "Creating test blockchain with a new account"
+mkdir test_data_dir
+geth --datadir test_data_dir --password .private_blockchain_password account new

scripts/start_private_blockchain

@@ -0,0 +1,2 @@
+#!/bin/bash
+geth --datadir test_data_dir --dev --nodiscover --mine --minerthreads 1 --maxpeers 0 --verbosity 3 --unlock 0 --password .private_blockchain_password --rpc