title: zombie browser won't open a window after calling open function
body: <p><strong>tools</strong></p>
  
  <p><strong>attempt 1</strong></p>
  
  <ul>
  <li>Darwin 14.3.0 Darwin Kernel Version 14.3.0</li>
  <li>io.js v1.8.1</li>
  <li>zombie Version 4.0.7 2015-04-10</li>
  </ul>
  
  <p><strong>attempt 2</strong></p>
  
  <ul>
  <li>Linux ubuntuG5 3.13.0-48-powerpc64-smp</li>
  <li>node.js v0.10.38</li>
  <li>zombie Version 3.1.0 2015-03-15</li>
  </ul>
  
  <p>commands:</p>
  
  <pre><code>const Browser = require('zombie');
  var url = 'https://google.com'
  var browser = new Browser();
  browser.open(url=url)
  browser.open('http://google.com', function(err) { browser.assert.success();
  });
  browser.assert.text('title', 'Google');
  </code></pre>
  
  <p>Results on both machines minus filepath differences:</p>
  
  <pre><code>    assert.js:93
    throw new assert.AssertionError({
          ^
  AssertionError: No open window with an HTML document
      at Browser.queryAll (/home/dmmmd/Dropbox/node_js_projects/node_modules/zombie/lib/index.js:432:5)
      at Assert.text (/home/dmmmd/Dropbox/node_js_projects/node_modules/zombie/lib/assert.js:307:33)
      at Object.&lt;anonymous&gt; (/home/dmmmd/Dropbox/node_js_projects/affinity-zombie/sample_zombie.js:7:16)
      at Module._compile (module.js:456:26)
      at Object.Module._extensions..js (module.js:474:10)
      at Module.load (module.js:356:32)
      at Function.Module._load (module.js:312:12)
      at Function.Module.runMain (module.js:497:10)
      at startup (node.js:119:16)
      at node.js:935:3
  </code></pre>
  
  <p>What am I missing after reading the docs at <a href="https://www.npmjs.com/package/zombie" rel="noreferrer">zombie browser</a>? Thanks in advance.</p>
  
  <p>I tried some other urls, too, even localhost ones without any success.</p>
  
  <p>JavaScript, node.js, io.js, and zombie are all new to me so I am basically just following recipes from the documentation and stackoverflow questions. I would appreciate any suggestions. I suspect I am missing something very simple.</p>