blocks/tag_youtube MDL-18974 - Switch to SimpleXML
blocks/tag_youtube MDL-18974 - Switch to SimpleXML

We use SimpleXML throughout Moodle now and its a dependency for Moodle 2.0.
It peforms better and allow us to remove another embeded library!

Also set the curl timeout on the youtube http requests so not to slow down
interactive page loads.

dilawar/moodle