AbyssalCraft 1.8.1

Major tweak and configuration version. This version focuses on tweaking
some features of the mod, while adding more configuration options. Also
includes more localization options in the .lang files, especially
messages sent through events in the mod (like the dialogue that appears
after Asorah has been defeated). The NEI (Not Enough Items) integration
and the Thaumcraft integrations have been bumped to the latest versions
of each mod.