Randomized boss fights and equipment use!

I made two new randomizations for you, both optional.

First, I added a randomization of boss fights. The main boss will still be there, but who joins that boss may be different from what you're used to!

Second, I added a randomization of who can equip what item. The hero is the slight exception; he still can equip all Zenithian equipment so you can get through the tower.

I also made a couple small bug fixes; you can take a look at those in the release notes. Enjoy! :)