remove tabs and fix jslint error
fixes #3352 - expose Piwik as an AMD module (uses the jQuery approach for backward compatibility)
update JSON implementation from 2012-10-08 version of json2.js; applied D.C.'s changes thru-out, including the defense against window.prototype (which I think refers to var declarations shadowing window.prototype)
update jslint to 2013-03-19
fix doc blocks
fix javascript tests (Firefox 20, Safari 6, Chrome 25)