title: wkhtmltopdf writes in apache error log for every pdf created
body: <p>Every time a PDF is created in WKHTMLTOPDF (using php) i am getting the following in the apache error log:</p>
  
  <pre><code>Loading pages (1/6)
  [&gt;                                                           ] 0%
  [======&gt;                                                     ] 10%
  [==========&gt;                                                 ] 17%
  [===================&gt;                                        ] 32%
  [==============================&gt;                             ] 50%
  [=====================================&gt;                      ] 63%
  [============================================&gt;               ] 74%
  [============================================================] 100%
  Counting pages (2/6)                                               
  [============================================================] Object 1 of 1
  Resolving links (4/6)                                                       
  [============================================================] Object 1 of 1
  Loading headers and footers (5/6)                                           
  Printing pages (6/6)
  [&gt;                                                           ] Preparing
  [============================================================] Page 1 of 1
  Done                                                                      
  </code></pre>
  
  <p>However the pdf is created without any errors, is there a way of stopping this as the error logs are getting very large and also masking genuine errors?</p>
  
  <p>Thanks </p>