remove ES6

Author: epoberezkin

.eslintrc.yml

@@ -4,7 +4,7 @@ extends: 'eslint:recommended'
 globals:
   Promise: false
 parserOptions:
-  ecmaVersion: 6
+  ecmaVersion: 5
 rules:
   indent: [ 2, 2, { SwitchCase: 1 } ]
   no-trailing-spaces: 2

lib/util.js

@@ -35,11 +35,13 @@ function objectToPromise(obj) {
   }
 
   return promises.length
-          ? Promise.all(promises).then(() => results)
+          ? Promise.all(promises).then(function() { return results; })
           : Promise.resolve(obj);
 
   function defer(p, _key) {
-    p = p.then((res) => { results[_key] = res; });
+    p = p.then(function (res) {
+      results[_key] = res;
+    });
     promises.push(p);
   }
 }