enable run reactive routing without BGP

   Another improment is: if we config interfaces for local subnet
   in network-cfg.json, sdn-ip will classify the traffic correctly

Change-Id: I94d80bc5a7c29b70e6c8546d99b71850cfb3f14d
diff --git a/apps/routing/src/main/java/org/onosproject/routing/config/impl/Configuration.java b/apps/routing/src/main/java/org/onosproject/routing/config/impl/Configuration.java
index 4520690..c58bc1b 100644
--- a/apps/routing/src/main/java/org/onosproject/routing/config/impl/Configuration.java
+++ b/apps/routing/src/main/java/org/onosproject/routing/config/impl/Configuration.java
@@ -32,8 +32,8 @@
 public class Configuration {
     // We call the BGP routers in our SDN network the BGP speakers, and call
     // the BGP routers outside our SDN network the BGP peers.
-    private List<BgpSpeaker> bgpSpeakers;
-    private List<BgpPeer> peers;
+    private List<BgpSpeaker> bgpSpeakers = Collections.emptyList();
+    private List<BgpPeer> peers = Collections.emptyList();
     private MacAddress virtualGatewayMacAddress;
 
     // All IP prefixes from the configuration are local