CC-5555 : Implement simple caching for preferences

using apc to save/fetch preferences to/from a cache.

airtime_mvc/application/models/Cache.php

@@ -0,0 +1,26 @@
+<?php
+
+class Cache
+{
+	
+	private function createCacheKey($key, $userId = null) {
+		
+		$CC_CONFIG = Config::getConfig();
+		$a = $CC_CONFIG["apiKey"][0];
+		$cacheKey = "{$key}{$userId}{$a}";
+		
+		return $cacheKey;
+	}
+	
+	public function store($key, $value, $userId = null) {
+		
+		$cacheKey = self::createCacheKey($key, $userId);
+		return apc_store($cacheKey, $value);
+	}
+	
+	public function fetch($key, $userId = null) {
+		
+		$cacheKey = self::createCacheKey($key, $userId);
+		return apc_fetch($cacheKey);
+	}
+}