Update Chess.java

implemented isChecked
Fix validMovement() defaulting to true
Merge branch 'stable'

Conflicts:
	pieces/Bishop.java
	pieces/Queen.java
Update Chess.java

Fixed isChecked() method
Update Chess.java

Fixed a bug where the King can not avoid check when the King moves to get out of check.
Fixed minor (major) bugs regarding movement
Added Comments to my SMH Code
Added canMove() method for the King
Fixed a Bug in canMove() 

The bug was that pieces surrounding the King were ignored.
Add validMove() method
Migrate validMove() to Chess;Fix indentation
Fixed Bugs related to isChecked().

Hopefully, check is finished here.
Implement checking system as well as user feedback
Fix canMove() method
Implement linear equation solver and add canIntercept() method to block piece checking king
Finish implementation of canIntercept(); Implement checkmate.
Update ToDo.txt
Implement En Passant, create checkedAfterMove() method, finish castling implementation
Fix problem with duplicate variable in subclass overriding superclass variable
Update ToDo.txt