[ONOS-5731] Implement skeleton of VirtualNetworkPacketManager

Changes
1. Added VirtualNetworkPacketManager
2. Added VirtualNetworkPacketStore interface and impl class
3. Added VirtualPacketStore impl
4. Simple test cases are added

Todo
1. More test cases

Change-Id: I86f0484a9ee038dab8716703f0e5e41cbcf30cb1
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualPacketProviderService.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualPacketProviderService.java
index 28272d6..9facc1b 100644
--- a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualPacketProviderService.java
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualPacketProviderService.java
@@ -15,7 +15,6 @@
  */
 package org.onosproject.incubator.net.virtual.provider;
 
-import org.onosproject.incubator.net.virtual.NetworkId;
 import org.onosproject.net.packet.PacketContext;
 
 /**
@@ -29,9 +28,8 @@
      * This processing will be done synchronously, i.e. run-to-completion.
      * This context is translated with virtual concepts.
      *
-     * @param networkId the virtual network ID which will handle the packet context
      * @param context inbound packet context
      */
-    void processPacket(NetworkId networkId, PacketContext context);
+    void processPacket(PacketContext context);
 
 }