remove background and foreground implementation, change convertion to bitarray to be done in show(), change sprite storage from strings to ints
remove background and foreground implementation, change convertion to bitarray to be done in show(), change sprite storage from strings to ints

scottsilverlabs/raspberrystem,scottsilverlabs/raspberrystem,scottsilverlabs/raspberrystem,scottsilverlabs/raspberrystem