Added 'use' option. Fix for PHP Strict (2048) error when calling listSou...

Added 'use' option. Fix for PHP Strict (2048) error when calling listSources without data. Usage instructions enhanced and clarified. Solves an error returning parameters from array when doing `elseif(count($args) > 2 && !empty($args[1])`.

Just a note, if following PSR standards, `null` should be lowercase