title: Ruby-Mp3Info error when saving/closing a file
body: <p>I've upgraded to the new mp3info GEM and now there seems to be a problem when it comes to writing the changes to the MP3 tags.  Ruby version 1.9.3, mp3info version 0.8.4, Windows 7 - 64 bit.</p>
  
  <p>Simple program:</p>
  
  <pre><code>require 'mp3info'
  mp3 = Mp3Info.open('a.mp3')
  mp3.title = 'bogo'
  mp3.close
  </code></pre>
  
  <p>Results in:</p>
  
  <pre><code>Errno::EACCES: Permission denied - (./.a.mp3.tmp, a.mp3)
  from D:/Ruby193/lib/ruby/gems/1.9.1/gems/ruby-mp3info-0.8.4/lib/mp3info.rb:453:in `rename'
  from D:/Ruby193/lib/ruby/gems/1.9.1/gems/ruby-mp3info-0.8.4/lib/mp3info.rb:453:in `close'
  from (irb):6
  from D:/Ruby193/bin/irb:12:in `&lt;main&gt;'
  </code></pre>
  
  <p>I've checked permissions on the file/folder, and I'm running as Administrator in the CMD shell.</p>