function inner_script_loaded(e) { 
			total--;
			if(total)
			{
				if(on_progress)
					on_progress(this.src, this.num);
			}
			else 
				inner_check_pending();
		}
Request script and inserts it in the DOM
@method requestScript
@param {String} url could be an array with urls to load in order
@param {Function} on_complete
@param {Function} on_error
@param {Function} on_progress (if several files are required, on_progress is called after every file is added to the DOM)