Yang Model Table View: skeleton code in place.

Change-Id: I836b00674d45ad5a4937bbb6c52be3df178a896e
diff --git a/apps/yms/gui/src/main/java/org/onosproject/yms/gui/YangModelUiComponent.java b/apps/yms/gui/src/main/java/org/onosproject/yms/gui/YangModelUiComponent.java
new file mode 100644
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+++ b/apps/yms/gui/src/main/java/org/onosproject/yms/gui/YangModelUiComponent.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright 2017-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.yms.gui;
+
+import com.google.common.collect.ImmutableList;
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onosproject.ui.UiExtension;
+import org.onosproject.ui.UiExtensionService;
+import org.onosproject.ui.UiMessageHandlerFactory;
+import org.onosproject.ui.UiView;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.List;
+
+import static org.onosproject.ui.UiView.Category;
+
+/**
+ * ONOS UI component for the Yang Models table view.
+ */
+@Component(immediate = true)
+public class YangModelUiComponent {
+
+    private static final ClassLoader CL =
+            YangModelUiComponent.class.getClassLoader();
+    private static final String VIEW_ID = "yangModel";
+    private static final String NAV_LABEL = "Yang Models";
+    private static final String NAV_ICON = "nav_yang";
+    private static final String HELP_URL =
+            "https://wiki.onosproject.org/display/ONOS/YANG+Models+in+ONOS";
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected UiExtensionService uiExtensionService;
+
+    // List of application views
+    private final List<UiView> uiViews = ImmutableList.of(
+            new UiView(Category.PLATFORM, VIEW_ID, NAV_LABEL, NAV_ICON, HELP_URL)
+    );
+
+    // Factory for UI message handlers
+    private final UiMessageHandlerFactory msgHandlerFactory =
+            () -> ImmutableList.of(
+                    new YangModelMessageHandler()
+            );
+
+    // Application UI Extension
+    private UiExtension extension =
+            new UiExtension.Builder(CL, uiViews)
+                    .resourcePath(VIEW_ID)
+                    .messageHandlerFactory(msgHandlerFactory)
+                    .build();
+
+    @Activate
+    protected void activate() {
+        uiExtensionService.register(extension);
+        log.info("Started");
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        uiExtensionService.unregister(extension);
+        log.info("Stopped");
+    }
+
+}