- Abstracts path creation logic

- Adds blank index.php to cache and temp folders
- Updates unit tests
- Extracts cache folder location from Renderer to Env class
- Implements #643

lib/Config/Renderer.php

@@ -16,7 +16,7 @@ class Renderer {
   function __construct($caching_enabled = false, $debugging_enabled = false) {
     $this->caching_enabled = $caching_enabled;
     $this->debugging_enabled = $debugging_enabled;
-    $this->cache_path = Env::$temp_path . '/cache';
+    $this->cache_path = Env::$cache_path;
 
     $file_system = new TwigFileSystem(Env::$views_path);
     $this->renderer = new TwigEnv(