Add test for object spread syntax

package.json

@@ -76,6 +76,7 @@
     "browser-unpack": "^1.1.1",
     "coffee-script": "~1.10.0",
     "coffeeify": "~1.1.0",
+    "has-object-spread": "^1.0.0",
     "has-template-literals": "^1.0.0",
     "isstream": "^0.1.2",
     "make-generator-function": "^1.1.0",

test/spread.js

@@ -0,0 +1,14 @@
+var browserify = require('../');
+var test = require('tap').test;
+var vm = require('vm');
+var hasObjectSpread = require('has-object-spread')();
+
+test('yield', { skip: !hasObjectSpread }, function (t) {
+    t.plan(2);
+    var b = browserify(__dirname + '/spread/main.js');
+
+    b.bundle(function (err, src) {
+        t.error(err);
+        t.notEqual(src.indexOf('...b'), -1, 'passed through spread syntax')
+    });
+});

test/spread/main.js

@@ -0,0 +1 @@
+var a = { ...b }