title: "Unsupported content-encoding: gzip,gzip" when submitting form with mechanize
body: <p>I'm trying to scrape some data using the mechanize library in ruby and I have to first get past a "Terms and Conditions" page. To that end I'm clicking an "I agree" button.</p>
  
  <pre><code>require 'mechanize'
  
  agent = Mechanize.new
  agent.agent.http.verify_mode = OpenSSL::SSL::VERIFY_NONE
  agent.get('https://apply.hobartcity.com.au/Common/Common/terms.aspx')
  
  form = agent.page.form_with(:id =&gt; 'aspnetForm')
  button = form.button_with(:name =&gt; 'ctl00$ctMain$BtnAgree')
  page = form.submit(button)
  </code></pre>
  
  <p>But when I run the above code I get this error on the form submission step:</p>
  
  <blockquote>
    <p>Uncaught exception: unsupported content-encoding: gzip,gzip</p>
  </blockquote>
  
  <p>When I access that second page with a browser the response headers are</p>
  
  <pre><code>HTTP/1.1 200 OK
  Cache-Control: private
  Content-Type: text/html; charset=utf-8
  X-UA-Compatible: IE=9,10,11
  Date: Tue, 16 Feb 2016 22:44:27 GMT
  Cteonnt-Length: 16529
  Content-Encoding: gzip
  Content-Length: 5436
  </code></pre>
  
  <p>I assume mechanize can work with <code>gzip</code> content encoding, so I'm not sure where the error is coming from. Any ideas what's going on here?</p>
  
  <p>Ruby 2.1.7, mechanize 2.7.4.</p>