Move budget outside of the core

The budget planning feature is now a plugin
See: https://github.com/kanboard/plugin-budget

app/Core/PluginLoader.php

@@ -20,13 +20,6 @@ class PluginLoader extends Base
      */
     const TABLE_SCHEMA = 'plugin_schema_versions';
 
-    /**
-     * Plugin folder
-     *
-     * @var string
-     */
-    const PATH = __DIR__.'/../../plugins';
-
     /**
      * Scan plugin folder and load plugins
      *
@@ -34,8 +27,8 @@ class PluginLoader extends Base
      */
     public function scan()
     {
-        if (file_exists(self::PATH)) {
-            $dir = new DirectoryIterator(self::PATH);
+        if (file_exists(__DIR__.'/../../plugins')) {
+            $dir = new DirectoryIterator(__DIR__.'/../../plugins');
 
             foreach ($dir as $fileinfo) {
                 if (! $fileinfo->isDot() && $fileinfo->isDir()) {