Transcode Skins and Capes for Java 5 Support

[catfromplan9]

Java 5 seems to struggle with viewing a lot of skins and capes, and they need to be transcoded to display in-game. Mojang's skin servers transcode skins and capes automatically, so this is a feature drasl lacks. Java 5 is the last version of Java supported on PowerPC architecture, and Minecraft versions up until 1.5.2 can support it. Currently drasl does not support pre-yggdrasil authentication so this issue was encountered when attempting to use a proxy I created, but it'd be nice to get this fixed before that changes so that anyone else running on obscure hardware will not encounter problems like this. The skins and capes that did not work were exported as a png from GIMP with the default settings. Here is a website that was able to transcode the skins into a format that worked: https://tinypng.com