Moved EventuallyConsistentMap classes into their own package.

Change-Id: I930a988a8cd8d47826a6f7d0f4ce23c56446df20
diff --git a/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapEvent.java b/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapEvent.java
new file mode 100644
index 0000000..ee7d42e
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapEvent.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright 2015 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.store.ecmap;
+
+import com.google.common.base.MoreObjects;
+
+import java.util.Objects;
+
+/**
+ * Event object signalling that the map was modified.
+ */
+public class EventuallyConsistentMapEvent<K, V> {
+
+    public enum Type {
+        PUT,
+        REMOVE
+    }
+
+    private final Type type;
+    private final K key;
+    private final V value;
+
+    /**
+     * Creates a new event object.
+     *
+     * @param type the type of the event
+     * @param key the key the event concerns
+     * @param value the value related to the key, or null for remove events
+     */
+    public EventuallyConsistentMapEvent(Type type, K key, V value) {
+        this.type = type;
+        this.key = key;
+        this.value = value;
+    }
+
+    /**
+     * Returns the type of the event.
+     *
+     * @return the type of the event
+     */
+    public Type type() {
+        return type;
+    }
+
+    /**
+     * Returns the key this event concerns.
+     *
+     * @return the key
+     */
+    public K key() {
+        return key;
+    }
+
+    /**
+     * Returns the value associated with this event.
+     *
+     * @return the value, or null if the event was REMOVE
+     */
+    public V value() {
+        return value;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (!(o instanceof EventuallyConsistentMapEvent)) {
+            return false;
+        }
+
+        EventuallyConsistentMapEvent that = (EventuallyConsistentMapEvent) o;
+        return Objects.equals(this.type, that.type) &&
+                Objects.equals(this.key, that.key) &&
+                Objects.equals(this.value, that.value);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, key, value);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .add("type", type)
+                .add("key", key)
+                .add("value", value)
+                .toString();
+    }
+}