Add AopAutoConfiguration (also starter and sample)

A side effect is that spring-boot-starter-data-jpa needs
to include an aspectjweaver depdendency. Hope that doesn't
hurt anything else.

[Fixes #56780004]

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/aop/AopAutoConfiguration.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2012-2013 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.boot.autoconfigure.aop;
+
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.reflect.Advice;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnExpression;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.EnableAspectJAutoProxy;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for Spring AOP.
+ * 
+ * @author Dave Syer
+ * @see EnableAspectJAutoProxy
+ */
+@Configuration
+@ConditionalOnClass({ EnableAspectJAutoProxy.class, Aspect.class, Advice.class })
+@ConditionalOnExpression("${spring.aop.auto:true}")
+public class AopAutoConfiguration {
+
+	@Configuration
+	@EnableAspectJAutoProxy(proxyTargetClass = false)
+	@ConditionalOnExpression("!${spring.aop.proxyTargetClass:false}")
+	public static class JdkDynamicAutoProxyConfiguration {
+	}
+
+	@Configuration
+	@EnableAspectJAutoProxy(proxyTargetClass = true)
+	@ConditionalOnExpression("${spring.aop.proxyTargetClass:false}")
+	public static class CglibAutoProxyConfiguration {
+	}
+
+}

spring-boot-autoconfigure/src/main/resources/META-INF/spring.factories

@@ -1,5 +1,6 @@
 # Auto Configure
 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
+org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,\
 org.springframework.boot.autoconfigure.MessageSourceAutoConfiguration,\
 org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration,\
 org.springframework.boot.autoconfigure.batch.BatchAutoConfiguration,\