title: Ruby open_uri error NoMethodError: undefined method `strip' for 10:Fixnum
body: <p>When I use this everything is fine:</p>
  
  <pre><code>html = open("http://"+self.url).read
  </code></pre>
  
  <p>But when I add a user agent:</p>
  
  <pre><code>html = open("http://"+self.url, "User-Agent" =&gt; "Ruby", 'read_timeout' =&gt; 10 ).read
  </code></pre>
  
  <p>I get:</p>
  
  <pre><code>NoMethodError: undefined method `strip' for 10:Fixnum
      from /Users/a_user/.rbenv/versions/2.2.3/lib/ruby/2.2.0/net/http/header.rb:17:in `block in initialize_http_header'
  </code></pre>
  
  <p>What is wrong here?</p>