Fixed bug that was never found by unit tests because unit tests are useless and only test what you know (aka what I already know works).  Also started fixing broken tests (once again, the tests themselves, not my code) before remembering I don't care.
Added knowledge which is what your currency is when you prestige.  You can buy stuff in the knowledge tab to unlock them in the game.  they will then appear in the game for you to purchase with money like normal items and upgrades.