Move inner classes to upper level

Rename as follows.
- ResourceId.Discrete -> DiscreteResourceId
- ResourceId.Continuous -> ContinuousResourceId
- Resource.Discrete -> DiscreteResource
- Resource.Continuous -> ContinuousResource

Change-Id: I80e59d1eec07128743bacc582a8725bd4d5489b4
diff --git a/core/api/src/main/java/org/onosproject/net/newresource/DiscreteResourceId.java b/core/api/src/main/java/org/onosproject/net/newresource/DiscreteResourceId.java
new file mode 100644
index 0000000..cf9d334
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/newresource/DiscreteResourceId.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.net.newresource;
+
+import com.google.common.annotations.Beta;
+import com.google.common.collect.ImmutableList;
+
+/**
+ * ResourceId for {@link DiscreteResource}.
+ *
+ * Note: This class is exposed to the public, but intended to be used in the resource API
+ * implementation only. It is not for resource API user.
+ */
+@Beta
+// TODO: consider how to restrict the visibility
+public final class DiscreteResourceId extends ResourceId {
+    DiscreteResourceId(ImmutableList<Object> components) {
+        super(components);
+    }
+
+    DiscreteResourceId() {
+        super();
+    }
+}