Pre-Omothol Update

This version (and 1.7.6/8/8.1) have been focused on implement some things before launching the 3rd and final dimension, Omothol. There has been a ton of tweaks and improvements to things in the mod, including an almost complete overhaul on the textures. The dimension has been released, but it currently isn't finished, so there's no structures nor mobs in there yet, but there will be in the next update, as that one will cover the end-game part of the mod, where you'll be able to face J'zahar. A large amount of configuration options have been implemented into the mod, allowing the user to tweak a lot more things through there. With the removal of AbyssalCraft Core, the internal API has been overhauled as well, creating an API that people can use if they want to add functionality from AbyssalCraft to their mod (where the current limit is the amount of stuff implemented into the API, which still isn't entirely complete).
Issues fixed:
#18, #19, #20, #21, #22
Suggestions implemented (that were suggested on github):
#17