Fixed placeholder scoreboard being super janky

Added missing import

Added some score stuff, starting to play with CSS stuff

Added the ability to lock tiles so they can't be flipped

Game difficulty is now changeable on the start page

Added more robust difficulty settings, the level now slightly influences the difficulty of the game

Fixed clicking header counting already-flipped tiles in its count of how many value tiles were found

Removed some comments

Header click is now conscious of pencil mode, moved the logic for game win/loss to their own functions

Fixed clicking headers preventing the game from recognizing when the user had won due to race conditions on the click events

Tried to fix some styling but it needs a lot of work

Double clicking a header now flips everything in the row/column

Fixed row/col input fields to not be super annoying to type in

Changed minimum row/col value to 3

Added min and max row/col values, fixed pressing the give up button not flipping the game is running flag to false