Add ability to remove patches

Change-Id: Ia777213f4e1a5c3f7b3b583b932dfea7590076f1
diff --git a/apps/patchpanel/src/main/java/org/onosproject/patchpanel/impl/PatchId.java b/apps/patchpanel/src/main/java/org/onosproject/patchpanel/impl/PatchId.java
new file mode 100644
index 0000000..d40cb21
--- /dev/null
+++ b/apps/patchpanel/src/main/java/org/onosproject/patchpanel/impl/PatchId.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016-present 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.patchpanel.impl;
+
+import org.onlab.util.Identifier;
+
+/**
+ * Identifier of a patch.
+ */
+public final class PatchId extends Identifier<Integer> {
+
+    private PatchId(int id) {
+        super(id);
+    }
+
+    /**
+     * Creates a new patch based of an integer.
+     *
+     * @param id backing value
+     * @return patch ID
+     */
+    public static PatchId patchId(int id) {
+        return new PatchId(id);
+    }
+}