[Persistence] Add persistence cache

Add a decorator to handle the caching of objects stored to
and/or read from persistence (bring over from pre-Angular
branch.) Supports the WARP Telemetry Adapter; the absence
of such a cache has been observed to result in significant
latency in instantiating autoflow tabular views for packets.
WTD-644.

Also, include an empty test file to ensure that the added
decorator is included in code coverage estimation (and to
provide a location for tests to be written later.)

platform/persistence/test/CachingPersistenceDecoratorSpec.js

@@ -0,0 +1,12 @@
+/*global define,Promise,describe,it,expect,beforeEach,waitsFor,jasmine*/
+
+define(
+    ["../src/CachingPersistenceDecorator"],
+    function (CachingPersistenceDecorator) {
+        "use strict";
+
+
+        describe("The caching persistence decorator", function () {
+        });
+    }
+);

platform/persistence/test/suite.json

@@ -1,4 +1,5 @@
 [
+    "CachingPersistenceDecorator",
     "CouchDocument",
     "CouchIndicator",
     "CouchPersistenceProvider"