My PocketMine plugins are bundled with a magic updater script.
It is really easy to update a plugin. All you need to do is open up a terminal window and enter
php [path to .phar]. The script will check for updates and inform you of any new versions.
Currently only a fraction of my plugins support the updater. The script was included in .phar files starting on November 22nd 2014 so only files created on that date or later will have the functionaility.