update solc version

Author: iurimatias

lib/core/config.js

@@ -79,7 +79,7 @@ Config.prototype.loadContractsConfigFile = function() {
   var configObject = {
     "versions": {
       "web3.js": "0.19.1",
-      "solc": "0.4.17"
+      "solc": "0.4.18"
     },
     "deployment": {
       "host": "localhost",