added error on pipe + callback
updated readme and changed libxmljs dependency version to *, as the older versions tent to give errors on a system with a newer/different version of libxml
updated readme
missing comma
reverted readme back to author's original
reverted readme back to author's original
Merge pull request #10 from fabdrol/master

Fixed an issue with an old version of libxmljs dependency, updated example in readme to use new callback style (err as first arg), and added fabdrol and mako-taco as collaborators in package.json.