Substantial refactoring to implement correct Naive, UCT Monte Carlo tree search methods.

Removed unnecessary distinction between policy and tree search (tree search is a special kind of policy).
Calculation of all valid moves / arbitrary sets of moves is now a seperate class, as it serves a different purpose than a policy.
Introduced regression error in AlphaBeta test.

test/net/woodyfolsom/msproj/IllegalMoveTest.java

@@ -0,0 +1,65 @@
+package net.woodyfolsom.msproj;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import net.woodyfolsom.msproj.GameBoard;
+import net.woodyfolsom.msproj.GameState;
+
+import org.junit.Test;
+
+public class IllegalMoveTest {
+	
+	@Test
+	public void testIllegalMoveOnOwnStone() {
+		GameState gameState = new GameState(5);
+		gameState.playStone('B', 3, GameBoard.BLACK_STONE);
+		assertFalse(gameState.playStone('B', 3, GameBoard.BLACK_STONE));
+	}
+	
+	@Test
+	public void testIllegalMoveOnOtherStone() {
+		GameState gameState = new GameState(5);
+		gameState.playStone('B', 3, GameBoard.BLACK_STONE);
+		assertFalse(gameState.playStone('B', 3, GameBoard.WHITE_STONE));
+	}
+	
+	@Test
+	public void testIllegalMoveNoLiberties() {
+		GameState gameState = new GameState(5);
+		gameState.playStone('A', 2, GameBoard.BLACK_STONE);
+		gameState.playStone('B', 3, GameBoard.BLACK_STONE);
+		gameState.playStone('B', 1, GameBoard.BLACK_STONE);
+		gameState.playStone('C', 2, GameBoard.BLACK_STONE);
+		assertFalse(gameState.playStone('B', 2, GameBoard.WHITE_STONE));
+		System.out.println(gameState);
+	}
+	
+	@Test
+	public void testIllegalMoveFormsTrappedGroup() {
+		GameState gameState = new GameState(9);
+		gameState.playStone('A', 5, GameBoard.BLACK_STONE);
+		gameState.playStone('B', 6, GameBoard.BLACK_STONE);
+		gameState.playStone('B', 7, GameBoard.BLACK_STONE);
+		gameState.playStone('A', 8, GameBoard.BLACK_STONE);
+		assertTrue(gameState.playStone('A', 6, GameBoard.WHITE_STONE));
+		assertFalse(gameState.playStone('A', 7, GameBoard.WHITE_STONE));
+		System.out.println(gameState);
+	}
+	
+	@Test
+	public void testIllegalMoveFormsTrappedGroup2() {
+		GameState gameState = new GameState(9);
+		gameState.playStone('G', 1, GameBoard.BLACK_STONE);
+		gameState.playStone('H', 2, GameBoard.BLACK_STONE);
+		gameState.playStone('H', 3, GameBoard.BLACK_STONE);
+		gameState.playStone('J', 4, GameBoard.BLACK_STONE);
+		gameState.playStone('A', 8, GameBoard.BLACK_STONE);
+		assertTrue(gameState.playStone('H', 1, GameBoard.WHITE_STONE));
+		assertTrue(gameState.playStone('J', 2, GameBoard.WHITE_STONE));
+		assertTrue(gameState.playStone('J', 3, GameBoard.WHITE_STONE));
+		System.out.println(gameState);
+		assertFalse(gameState.playStone('J', 1, GameBoard.WHITE_STONE));
+		System.out.println(gameState);
+	}
+}