title: Invalid XSD schema using libxmljs with nodejs
body: <p>I've posted an issue on libxmljs repository and it was closed because they think that this isn't a problem at the level of the lib. So I post it here.</p>
  
  <p>I'm trying to validate a XLIFF file with a XML schema provided by OASIS but I keep receiving an error with the XSD.</p>
  
  <blockquote>
    <p>Error: Invalid XSD schema
       at Document.validate (/Users/fluxb0x/Tests/xliff_parser/node_modules/libxmljs/lib/document.js:73:17)
       at Request._callback (/Users/fluxb0x/Tests/xliff_parser/main.js:25:21)
       at Request.self.callback (/Users/fluxb0x/Tests/xliff_parser/node_modules/request/request.js:199:22)
       at Request.emit (events.js:98:17)
       at Request. (/Users/fluxb0x/Tests/xliff_parser/node_modules/request/request.js:1160:14)
       at Request.emit (events.js:117:20)
       at IncomingMessage. (/Users/fluxb0x/Tests/xliff_parser/node_modules/request/request.js:1111:12)
       at IncomingMessage.emit (events.js:117:20)
       at _stream_readable.js:938:16
       at process._tickCallback (node.js:419:13)</p>
  </blockquote>
  
  <p>I've use Oxygen XML editor to test the validation and it goes without problem.</p>
  
  <p>This is the XLIFF file exported by me : <a href="https://gist.github.com/igorissen/ab758735ee91bc233424#file-en-xliff" rel="nofollow">en.xliff</a></p>
  
  <p>This is the XSD file provided by OASIS : <a href="https://gist.github.com/igorissen/ab758735ee91bc233424#file-xliff_schema-xsd" rel="nofollow">xliff_schema.xsd</a></p>
  
  <p>Pretty big file.</p>
  
  <p>Thank you for the help.</p>