fix error message that print undefined

lib/core/logger.js

@@ -1,7 +1,6 @@
 require('colors');
 let fs = require('./fs.js');
 const date = require('date-and-time');
-const constants = require('../constants');
 
 const DATE_FORMAT = 'YYYY-MM-DD HH:mm:ss:SSS';
 const LOG_REGEX = new RegExp(/\[(\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d:\d\d\d)\] (?:\[(\w*)\]:?)?\s?\s?(.*)/gmi);

lib/modules/blockchain_connector/index.js

@@ -538,8 +538,8 @@ class BlockchainConnector {
       function(next) {
         async.times(limit, function(n, eachCb) {
           self.web3.eth.getBlock(from - n, returnTransactionObjects, function(err, block) {
-            if (err) {
-              self.logger.error(err);
+            if (err && err.message) {
+              // FIXME Returns an error because we are too low
               return eachCb();
             }
             blocks.push(block);