Relocate dependencies within the processor jar

[SquidDev]

If an annotation processor depends on a more recent version of one of Mixin's dependencies, it's possible that the outdated class from Mixin's processor jar will be used instead, resulting in NoSuchMethodErrors during compilation.

Instead, we relocate the shadowed dependencies to live within the org.spongepowered.asm.shadow package instead, allowing them to co-exist with other processors.