/**
* Formats a file size as b, Kb, Mb etc
* @param (number) size File size in bytes
* @param (number) dec Number of decimal points to round to
*/
function formatFileSize(size, dec)
{
	if(isNaN(dec)) dec = 2;
	var multiply = Math.pow(10, dec);
	var units = ['b','Kb','Mb','Gb','Tb','Pb'];
	var exponent = Math.floor(Math.log(size)/Math.log(1024));
	return (Math.round(size/Math.pow(1024, exponent) * multiply) / multiply) + units[exponent];
}