title: How do I send utf-8 data using pika?
body: <p>I am trying to post a unicode string over pika. When I send it I get this message:</p>
  
  <pre><code>UnicodeEncodeError: 'ascii' codec can't encode characters in position 6-20: ordinal not in range(128)
      self.write(data)
    File "/usr/lib/python2.7/site-packages/pika/simplebuffer.py", line 62, in write
      self.buf.write(data)
  </code></pre>
  
  <p>Looking around, it seems I have to set the charset or content type to UTF-8 using pika.BasicProperties, but i can't find documentation on that class.</p>
  
  <p>What should I set to post unicode data?</p>