Implement groups CLI command autocompletion

Change-Id: I0bb9eff30c03a5d08f69280879ec2be869cb6539
diff --git a/cli/src/main/java/org/onosproject/cli/net/GroupStatusCompleter.java b/cli/src/main/java/org/onosproject/cli/net/GroupStatusCompleter.java
new file mode 100644
index 0000000..4042138
--- /dev/null
+++ b/cli/src/main/java/org/onosproject/cli/net/GroupStatusCompleter.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.cli.net;
+
+import com.google.common.collect.Lists;
+import org.onosproject.cli.AbstractChoicesCompleter;
+import org.onosproject.net.group.Group;
+
+import java.util.List;
+
+/**
+ * Group status completer.
+ */
+public class GroupStatusCompleter extends AbstractChoicesCompleter {
+    @Override
+    protected List<String> choices() {
+        List<String> strings = Lists.newArrayList();
+        for (Group.GroupState groupState : Group.GroupState.values()) {
+            strings.add(groupState.toString());
+        }
+        strings.add(GroupsListCommand.ANY);
+        return strings;
+    }
+}