Fixed some issues in chess.py

[ABarpanda]

As mentioned in issue #534
There are many problems

1. The pawn doesn't move 2 steps
2. There is no checkmateExists function as mentioned
3. The first move is made by black instead of white
4. The positions of king and queen are wrong in black
5. When we enter a valid move, all the pieces are printed individually
6. There is no option to end the game in between. The only option is to kill the program.
7. The pawn moves out of the board

Problems solved

• Now the pawn moves 2 steps on its first step
• The first move is now made by white
• The kings and queens are now correctly placed
• A pawn does not move out of the board
• Problem 5 eliminated

[ABarpanda]

I also added some improvements to the book-cricket-game. It is also included in the pull request.
It is explained in #539