Add initial implementation of database and HTML loader classes

public/html_loader.php

@@ -0,0 +1,22 @@
+<?php
+class HTMLLoader {
+    private $template;
+
+    function __construct() {
+        // Check if Paths variables exists
+        if (!defined(TEMPLATE_PATH) || !defined(TEMPLATE_CONF)) {
+            die("TEMPLATE_PATH or TEMPLATE_CONF are not defined at " . __FILE__);
+        }
+    }
+    
+    function setTemplate($template) {
+        // Check if template exists
+        $file = file_get_contents(TEMPLATE_CONF);
+        $json = json_decode($file, true);
+
+        if (!array_key_exists($template, $json) && array_key_exists("error", $json)) {
+            $this->showError('Template "' . $template . '" was not found.');
+            
+        } 
+    }
+}