Merge pull request #346 from maxharlow/master

Promise needs to be returned

Author: apocas

lib/docker.js

@@ -302,7 +302,7 @@ Docker.prototype.buildImage = function(file, opts, callback) {
     pack.finalize();
     pack.pipe(zlib.createGzip()).pipe(concat(build));
   } else {
-    build(file);
+    return build(file);
   }
 };