Bug fix for IgnoreDhcp rules after switch restart. Also fixed NPE in group handler,
and made recognizing ofdpa software more generic to handle premium versions on accton switches.

Change-Id: Ie1f40dd934c2a1adb75174c90c2d6f1b71f98d3a
diff --git a/apps/dhcprelay/src/main/java/org/onosproject/dhcprelay/Dhcp4HandlerImpl.java b/apps/dhcprelay/src/main/java/org/onosproject/dhcprelay/Dhcp4HandlerImpl.java
index 2c8cf92..d715c06 100644
--- a/apps/dhcprelay/src/main/java/org/onosproject/dhcprelay/Dhcp4HandlerImpl.java
+++ b/apps/dhcprelay/src/main/java/org/onosproject/dhcprelay/Dhcp4HandlerImpl.java
@@ -243,6 +243,17 @@
         });
     }
 
+    @Override
+    public void removeIgnoreVlanState(IgnoreDhcpConfig config) {
+        if (config == null) {
+            ignoredVlans.clear();
+            return;
+        }
+        config.ignoredVlans().forEach((deviceId, vlanId) -> {
+            ignoredVlans.remove(deviceId, vlanId);
+        });
+    }
+
     public void setDhcpServerConfigs(Collection<DhcpServerConfig> configs, List<DhcpServerInfo> serverInfoList) {
         if (configs.size() == 0) {
             // no config to update