title: Pylatex error when generate PDF file - No such file or directory
body: <p>I just want to use Pylatex to generate the pdf file. I look at the basic example and re-run the script but it raised the error: OSError: [Errno 2] No such file or directory.</p>
  
  <p>Here is my script:</p>
  
  <pre><code>import sys
  from pylatex import Document, Section, Subsection, Command
  from pylatex.utils import italic, NoEscape
  
  
  def fill_document(doc):
      """Add a section, a subsection and some text to the document.
      :param doc: the document
      :type doc: :class:`pylatex.document.Document` instance
      """
      with doc.create(Section('A section')):
          doc.append('Some regular text and some ')
          doc.append(italic('italic text. '))
  
          with doc.create(Subsection('A subsection')):
              doc.append('Also some crazy characters: $&amp;#{}')
  
  
  if __name__ == '__main__':
      reload(sys)
      sys.setdefaultencoding('utf8')
      # Basic document
      doc = Document()
      fill_document(doc)
  
      doc.generate_pdf("full")
      doc.generate_tex()
  </code></pre>
  
  <p>And the error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "/Users/code/Test Generator/Generate.py", line 34, in &lt;module&gt;
      doc.generate_pdf("full")
    File "/Library/Python/2.7/site-packages/pylatex/document.py", line 227, in generate_pdf
      raise(os_error)
  OSError: [Errno 2] No such file or directory
  </code></pre>
  
  <p>Can someone help me ? :-D thanks a lot.</p>