Check must prevent castling
Prevent castling if under check.
Proving that check is preventing castling just temporarily
Test fpr prohibiting castling if crossing attacked square
Particular 'crossing of attacked square' validation
Covering 'crossed' cases.
Refactoring: reduce complexity of inner if's
TODO
King cannot move under check
Refactoring: removed code that was already covered in another place (and easier): code that checks if the king is not exposed to check by the move.
Intermediate pieces mustn't allow castling
Queen-side check for obstacles to castle
King-side occupied prevents castling
+1 test
Inlining
Merge pull request #92 from lrozenblyum/KingMovement

King movement