Moved BGP code and Router code into their own bundle.

The main goal of this is to allow routing code to be used by multiple
applications.

Changes include:
 * Created an onos-app-routing bundle and moved BGP code and routing code
   into it.
 * Created an onos-app-routing-api bundle as a common API bundle between
   onos-app-routing and onos-app-sdnip, to prevent circular dependencies.
 * Moved API classes into onos-app-routing-api bundle.
 * Made Router and BgpSessionManager into OSGi components. This is not quite
   clean, because there is still a chain of start() method calls from SdnIp
   through to BgpSessionManager to preserve startup order. This should be
   revisted so components can be started using activate()
 * Created BgpService and RoutingService APIs to glue different components
   together.
 * Many unit test changes. A lot of the previous unit tests spanned the
   Router and IntentSynchronizer classes, but this is not possible any more
   since these classes are in different bundles. I had to rewrite some of
   these tests so that each unit test class only tests one real class. A
   nice side-effect is that the tests are now simpler because each test
   tests less functionality.
 * Removed SdnIp test seeing as it doesn't run automatically, was already
   broken and has been largely superseded by other unit tests and the nightly
   functional tests.

Change-Id: I70ecf5391aa353e99e7cdcf7ed38a530c87571bb
diff --git a/apps/routing-api/src/main/java/org/onosproject/routingapi/BgpService.java b/apps/routing-api/src/main/java/org/onosproject/routingapi/BgpService.java
new file mode 100644
index 0000000..c7e58d4
--- /dev/null
+++ b/apps/routing-api/src/main/java/org/onosproject/routingapi/BgpService.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * 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.onosproject.routingapi;
+
+/**
+ * Provides a way of interacting with the BGP protocol component.
+ */
+public interface BgpService {
+
+    /**
+     * Starts the BGP service.
+     *
+     * @param routeListener listener to send route updates to
+     * @param bgpPort port number to listen on
+     */
+    void start(RouteListener routeListener, int bgpPort);
+
+    /**
+     * Stops the BGP service.
+     */
+    void stop();
+}