Added @Beta annotations to the network configuration API.

Change-Id: I6b0e4f2064509a26e546735baef087e621ad8307
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/config/NetworkConfigRegistry.java b/incubator/api/src/main/java/org/onosproject/incubator/net/config/NetworkConfigRegistry.java
index 76e9bab..261e1bd 100644
--- a/incubator/api/src/main/java/org/onosproject/incubator/net/config/NetworkConfigRegistry.java
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/config/NetworkConfigRegistry.java
@@ -15,11 +15,14 @@
  */
 package org.onosproject.incubator.net.config;
 
+import com.google.common.annotations.Beta;
+
 import java.util.Set;
 
 /**
  * Service for tracking network configuration factories.
  */
+@Beta
 public interface NetworkConfigRegistry {
 
     /**