General improvements including boss fight and environment

Demon's Wrath · build 11494142 · published

On SteamNotes only · this build shipped before we watched the app

improved grass, added in-game item store (press esc), updated start menu, improved boss fight, added some kind of collapsed cave for Robert's dad, added footstep sound, background tracks, and boss fight track. Also changed the way quest data is stored to make it more futureproof - old saves will not work with this new version.