EnumState isSimple() returns wrong value

- Fix wrong boolean return value.
- Fixes #66

spring-statemachine-core/src/main/java/org/springframework/statemachine/state/AbstractState.java

@@ -201,7 +201,7 @@ public abstract class AbstractState<S, E> implements State<S, E> {
 
 	@Override
 	public boolean isSimple() {
-		return isSubmachineState() && isComposite();
+		return !isSubmachineState() && !isComposite();
 	}
 
 	@Override

spring-statemachine-core/src/test/java/org/springframework/statemachine/state/EnumStateTests.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2015 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.statemachine.state;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+import org.springframework.statemachine.AbstractStateMachineTests.TestEvents;
+import org.springframework.statemachine.AbstractStateMachineTests.TestStates;
+
+public class EnumStateTests {
+
+	@Test
+	public void testSimpleEnumState() {
+		State<TestStates,TestEvents> stateSI = new EnumState<TestStates,TestEvents>(TestStates.SI);
+		assertThat(stateSI.isSimple(), is(true));
+		assertThat(stateSI.isComposite(), is(false));
+		assertThat(stateSI.isOrthogonal(), is(false));
+		assertThat(stateSI.isSubmachineState(), is(false));
+	}
+
+}