Eubos v2.15

Full Changelog: v2.14...v2.15

I have completely reworked the internal position storage from 0x88 and bitboards to bit offset and bitboards. I have also reworked the hash table to use a tradiitonal indexed array system (previously it used a queue). Furthermore I have implemented a pawn hash array and tweaked a couple of evaluation parameters. Despite all this, v2.15 is not much stronger than v2.14.