Implement a Connect 4 game. The program should allow two players to play each other. For each turn, have the user enter the column they want to play in, validate the user has made a good move, and then place the piece on the board. Then the program should check for a winner and a tie, and assuming there is neither, redisplay the board and get the next players move. Display the moves using print/println commands, and use an X for player 1 and an O for player 2. When the game ends, the program should display congratulations to the winner or announce there was a tie, and then allow the players to choose to play again or exit.