refactor winnable_combinations in board_state, add BoardNotSquareError because the new implementation requires converting a float to an int
rename AlertStore to RawAlertsStore
add player order chosen at random message to the instructions screen
fix bug where program would crash if screen was smaller than content
extract the empty cell value into a constant
centralize creation of empty boards in BoardState
tiny modification
ui does not accept screen resize event when waiting for input on alert screens
screen displays portions of content instead of mangling it via wrapping when its dimensions are smaller than the content
message change