Revert:
https://github.com/xGhOsTkiLLeRx/SilkSpawners/commit/6ddf2b1240ef2505b6573fe1620633712417eeea

The plugin will break anyways between each Minecraft Update - this means
the option to change the internal field values is obsolete, because I
have to update the imports [or need to bypass it].
Between minor updates the code shouldn't change and CraftBukkits
variables should normally remain the same.

This also restores MCPC+ compatibility because the own remapper only
accepts "literal constants" and no config values. (Thanks @agaricusb for
explaining this!)

However, I still need to test these builds with other CraftBukkit forks.