Update un-renamed but shade-relocated mapping

Now outputting all class names in mappings generated by SpecialSource 1.3
snapshot, even if they are not renamed. Avoids need to special-case
net.minecraft.server.MinecraftServer in code.
Remap plugins using Bouncycastle to Forge, not vanilla. Closes #133.

The obfuscated copy of Bouncycastle included in vanilla Minecraft
is not in MCPC+, and isn't used by Forge - which has its own, more
complete, non-obfuscated copy of Bouncycastle.

However, the cb2obf mappings were remapping Bouncycastle to the
obfuscated version, causing class not found errors if plugins use it.
The added package remap takes precedence over the class remaps,
and fixes the missing references when plugins use Bouncycastle.

Test case: https://github.com/agaricusb/IncompatiblePlugin/commit/f86dd89cb955b9d4919bda7bdbbc43359dd43058