Added Cache::setKey() to allow dynamic setting of cache key

system/src/Grav/Common/Cache.php

@@ -263,6 +263,15 @@ class Cache extends Getters
         return $this->key;
     }
 
+    /**
+     * Setter method to set key (Advanced)
+     */
+    public function setKey($key)
+    {
+        $this->key = $key;
+        $this->driver->setNamespace($this->key);
+    }
+
     /**
      * Helper method to clear all Grav caches
      *