Remove unused Cache class

Kabuki CMS uses a Cache class to cache objects using APCU, but Pics has never used it.

models/Cache.php

@@ -1,61 +0,0 @@
-<?php
-/*****************************************************************************
- * Cache.php
- * Contains key class Cache.
- *
- * Kabuki CMS (C) 2013-2015, Aaron van Geffen
- *****************************************************************************/
-
-class Cache
-{
-	public static $hits = 0;
-	public static $misses = 0;
-	public static $puts = 0;
-	public static $removals = 0;
-
-	public static function put($key, $value, $ttl = 3600)
-	{
-		// If the cache is unavailable, don't bother.
-		if (!CACHE_ENABLED || !function_exists('apcu_store'))
-			return false;
-
-		// Keep track of the amount of cache puts.
-		self::$puts++;
-
-		// Store the data in serialized form.
-		return apcu_store(CACHE_KEY_PREFIX . $key, serialize($value), $ttl);
-	}
-
-	// Get some data from the cache.
-	public static function get($key)
-	{
-		// If the cache is unavailable, don't bother.
-		if (!CACHE_ENABLED || !function_exists('apcu_fetch'))
-			return false;
-
-		// Try to fetch it!
-		$value = apcu_fetch(CACHE_KEY_PREFIX . $key);
-
-		// Were we successful?
-		if (!empty($value))
-		{
-			self::$hits++;
-			return unserialize($value);
-		}
-		// Otherwise, it's a miss.
-		else
-		{
-			self::$misses++;
-			return null;
-		}
-	}
-
-	public static function remove($key)
-	{
-		if (!CACHE_ENABLED || !function_exists('apcu_delete'))
-			return false;
-
-		self::$removals++;
-		return apcu_delete(CACHE_KEY_PREFIX . $key);
-	}
-}