Refactors IGMPProxy application in API and APP bundles

Change-Id: I465d6c0f49079804ae8e0a1f464581c25c6d2300
diff --git a/app/src/main/java/org/opencord/igmpproxy/impl/OsgiPropertyConstants.java b/app/src/main/java/org/opencord/igmpproxy/impl/OsgiPropertyConstants.java
new file mode 100644
index 0000000..94300b5
--- /dev/null
+++ b/app/src/main/java/org/opencord/igmpproxy/impl/OsgiPropertyConstants.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2019-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.opencord.igmpproxy.impl;
+
+/**
+ * Constants for default values of configurable properties.
+ */
+public final class OsgiPropertyConstants {
+
+    private OsgiPropertyConstants() {
+    }
+
+    public static final String STATISTICS_GENERATION_PERIOD = "statisticsGenerationPeriodInSeconds";
+    public static final int STATISTICS_GENERATION_PERIOD_DEFAULT = 20;
+
+}