Initial port of the YouTube plugin.
YouTube: Changed indentation from tabs to spaces.
Use DDG.load instead of DDG.require on the YouTube plugin.

- DDG.require was renamed to DDG.load.
Changed DDG.load to $.getScript.
Added loadJS function in the YouTube plugin.

We don't have jQuery yet, so it's best to put loadJS here at the moment.
Merge branch 'master' of github.com:duckduckgo/zeroclickinfo-spice