Fix pull with callback only (#158)

Author: Gaëtan Faramaz

lib/pull.js

@@ -10,6 +10,11 @@ module.exports = function (remote, branch, opt, cb) {
     cb = opt;
     opt = {};
   }
+  // pull with callback only
+  if (!cb && typeof remote === 'function') {
+    cb = remote;
+    remote = {};
+  }
   if (!cb || typeof cb !== 'function') cb = function () {};
   if (!opt) opt = {};
   if (!opt.cwd) opt.cwd = process.cwd();