Polished BMv2 protocol module

- Improved and fixed typos in javadocs
- Added missing beta API annotations
- Refactored the default interpreter implementation

Change-Id: Ibfb21d31415d8f25cc67307f8bea2871951c9a8f
diff --git a/protocols/bmv2/api/src/main/java/org/onosproject/bmv2/api/service/Bmv2PacketListener.java b/protocols/bmv2/api/src/main/java/org/onosproject/bmv2/api/service/Bmv2PacketListener.java
index a713dd8..32629eb 100644
--- a/protocols/bmv2/api/src/main/java/org/onosproject/bmv2/api/service/Bmv2PacketListener.java
+++ b/protocols/bmv2/api/src/main/java/org/onosproject/bmv2/api/service/Bmv2PacketListener.java
@@ -16,12 +16,14 @@
 
 package org.onosproject.bmv2.api.service;
 
+import com.google.common.annotations.Beta;
 import org.onlab.util.ImmutableByteSequence;
 import org.onosproject.bmv2.api.runtime.Bmv2Device;
 
 /**
  * A listener of BMv2 packet events.
  */
+@Beta
 public interface Bmv2PacketListener {
 
     /**