Gradle Building

Allows for IronChests to be able to build with nothing but gradle and an internet connection, provided MavenCentral is up and stuff.

simply run ```gradle build``` to setup the minecraft workspace and compile the mod to a reobfuscated jar outputted to 'build/libs'

Your old versioning system has been ported over to gradle, but it could use a bit of tweaking to make it more efficient.

I have taken the liberty of having the buildcsrtipt output both a javadoc and sources jar along with the reobfuscated jar. By default the jar is obfuscated to SRG names, though there is support for obfuscating directly to minecraft names as well.

If you want me to include the gradle wrapper, let me know.