INT-2626 Fix RLR parser

Fix RecipientListRouterParser to extend
from AbstractRouterParser, thus eliminating
the problem described in INT-2626.

Previously, the router was a top level bean and, since
it is an @ManagedResource, the mbean exporter eagerly
instantiated it (and its Recipients) before the
ChannelInitializer ran.

Now, it is an anonymous inner bean inside a FB,
so the exporter no longer "finds" it,
thus deferring the Recipient instantiation
until the router itself is instantiated via its FB,
which will be after the C.I. runs.

This is all fine, with one caveat - previously the RLR
is made available as an MBean - now it is not,
unless you ALSO add the int-jmx:mbean-exporter.

However, the MBean is very basic, with no attributes and
a single operation 'setShouldTrack()', so the risk is
extremely low and the workaround is to add the
IntegrationMBeanExporter.

INT-2626 polished based on PR comments

spring-integration-jmx/src/test/java/org/springframework/integration_/mbeanexporterhelper/INT-2626-config.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:context="http://www.springframework.org/schema/context"
+	xmlns:int-jmx="http://www.springframework.org/schema/integration/jmx"
+	xmlns:int="http://www.springframework.org/schema/integration"
+	xsi:schemaLocation="http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
+		http://www.springframework.org/schema/integration/jmx http://www.springframework.org/schema/integration/jmx/spring-integration-jmx.xsd
+		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
+		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
+
+	<context:mbean-server />
+	<context:mbean-export />
+
+	<int:recipient-list-router input-channel="command"
+		default-output-channel="nullChannel">
+		<int:recipient channel="controlBusChannel"
+			selector-expression="payload.contains('stop')" />
+	</int:recipient-list-router>
+
+	<int:control-bus input-channel="controlBusChannel" />
+
+</beans>

spring-integration-jmx/src/test/java/org/springframework/integration_/mbeanexporterhelper/INT_2626Tests.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2002-2012 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.integration_.mbeanexporterhelper;
+
+import org.junit.Test;
+import org.springframework.context.support.ClassPathXmlApplicationContext;
+
+/**
+ * @author Oleg Zhurakousky
+ *
+ */
+public class INT_2626Tests {
+
+	@Test // This context failed to load before the INT-2626 fix was applied
+	public void testInt2626(){
+		new ClassPathXmlApplicationContext("INT-2626-config.xml", this.getClass());
+	}
+}