Detangling incubator: virtual nets, tunnels, resource labels, oh my

- virtual networking moved to /apps/virtual; with CLI & REST API
- tunnels and labels moved to /apps/tunnel; with CLI & REST API; UI disabled for now
- protobuf/models moved to /core/protobuf/models
- defunct grpc/rpc registry stuff left under /graveyard
- compile dependencies on /incubator moved to respective modules for compilation
- run-time dependencies will need to be re-tested for dependent apps

- /graveyard will be removed in not-too-distant future

Change-Id: I0a0b995c635487edcf95a352f50dd162186b0b39
diff --git a/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/IntentDomain.java b/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/IntentDomain.java
new file mode 100644
index 0000000..7060104
--- /dev/null
+++ b/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/IntentDomain.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.incubator.net.domain;
+
+import com.google.common.annotations.Beta;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+
+import java.util.Set;
+
+/**
+ * Representation of an intent domain which includes the set of internal devices,
+ * the set of edge ports, and the implementation of the domain provider.
+ */
+@Beta
+public class IntentDomain {
+
+    private final IntentDomainId id;
+    private String name;
+
+    private Set<DeviceId> internalDevices;
+    private Set<ConnectPoint> edgePorts;
+
+    private IntentDomainProvider provider;
+
+    public IntentDomain(IntentDomainId id, String name,
+                 Set<DeviceId> internalDevices,
+                 Set<ConnectPoint> edgePorts) {
+        this.id = id;
+        this.name = name;
+        this.internalDevices = internalDevices;
+        this.edgePorts = edgePorts;
+    }
+
+    /**
+     * Returns the id for the intent domain.
+     *
+     * @return intent domain id
+     */
+    public IntentDomainId id() {
+        return id;
+    }
+
+    /**
+     * Returns the friendly name for the intent domain.
+     *
+     * @return intent domain name
+     */
+    public String name() {
+        return name;
+    }
+
+    /**
+     * Returns the set of internal devices for the intent domain (devices under
+     * exclusive control of the intent domain).
+     *
+     * @return set of internal devices
+     */
+    public Set<DeviceId> internalDevices() {
+        return internalDevices;
+    }
+
+    /**
+     * Returns the set of edge ports for the intent domain.
+     *
+     * @return set of edge ports
+     */
+    public Set<ConnectPoint> edgePorts() {
+        return edgePorts;
+    }
+
+    /**
+     * Returns the provider for the intent domain.
+     *
+     * @return intent domain provider
+     */
+    public IntentDomainProvider provider() {
+        return provider;
+    }
+
+    /**
+     * Returns the status of the intent domain. An intent domain is active if it
+     * has an intent domain provider bound, and it is inactive if one is not bound.
+     *
+     * @return true if active; false otherwise
+     */
+    public boolean isActive() {
+        return provider != null;
+    }
+
+    /**
+     * Sets the provider for the intent domain if one is not already set.
+     *
+     * @param provider new intent domain provider
+     */
+    public void setProvider(IntentDomainProvider provider) {
+        // TODO consider checkState depending on caller
+        if (this.provider == null) {
+            this.provider = provider;
+        }
+    }
+
+    /**
+     * Unsets the provider for the intent domain.
+     */
+    public void unsetProvider() {
+        this.provider = null;
+    }
+
+    //TODO add remaining setters (we will probably want to link this to the network config)
+}