fix possible double callback

Author: jrainville

lib/contracts/deploy_manager.js

@@ -133,20 +133,22 @@ class DeployManager {
           return callback(new Error("error running afterDeploy"));
         }
 
-        // TODO: convert to for to avoid repeated callback
-        for(let cmd of onDeployCode) {
+        async.each(onDeployCode, (cmd, eachCb) => {
           self.logger.info("executing: " + cmd);
           try {
             RunCode.doEval(cmd, web3);
           } catch(e) {
             if (e.message.indexOf("invalid opcode") >= 0) {
               self.logger.error('the transaction was rejected; this usually happens due to a throw or a require, it can also happen due to an invalid operation');
             }
-            return callback(new Error(e));
+            return eachCb(new Error(e));
           }
-        }
+          eachCb();
+        }, (err) => {
+          callback(err, contractsManager);
+        });
+
 
-        callback(null, contractsManager);
       }
     ], function (err, result) {
       if (err) {