Add MCP mappings
Use FML's copy of the argo library instead of obfuscated version

Remove argo from MCP reobfuscation since Mojang's obfuscated version
is not used, in favor of FML's complete and non-obfuscated copy.
Pre-deobfuscate server. Fixes loading version-independent mods.

Requires latest SpecialSourceMP snapshot for finalName support.
Now able to load at least IronChests 5.
This change does not add support for loading obfuscated mods.