Wrong symbols used for byte conversion

[sreichel]

$symbol = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
$exp = floor(log($bytes) / log(1024));

Technically, these are the wrong symbols, (KB=1000, KiB=1024) but that might be for another time

Originally posted by @Hanmac in #4693 (comment)