Download largest version

[dshackith]

Every emoticon has a standard version (used in the client) as well as a 2x and 4x version which can be accessed by inserting @2x between the file name and the file extension (e.g. zoidberg-1417754444.png is the standard version but you can get the largest by using [email protected] in the request). This is standard for all emoticons, so it should be able to be handled by the script.