Add autoconfig support for Flyway migrations

Flyway starts up with its default settings if it is on the classpath.
You can also ask Boot to barf if the migration scripts are missing.

Fixes gh-730

spring-boot-samples/spring-boot-sample-flyway/src/test/java/sample/flyway/SampleLiquibaseApplicationTests.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2012-2014 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 sample.flyway;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(classes=SampleFlywayApplication.class)
+public class SampleLiquibaseApplicationTests {
+	
+	@Autowired
+	private JdbcTemplate template;
+	
+	@Test
+	public void testDefaultSettings() throws Exception {
+		assertEquals(new Integer(1), template.queryForObject("SELECT COUNT(*) from PERSON", Integer.class));
+	}
+
+}