Revert "Add upgrade class for data migration"

This reverts commit e6245be4a3.

admin/core/packages/1.3.39.php

@@ -1,27 +0,0 @@
-<?php 
-	
-	// If this file is called directly, abort.
-	if ( ! defined( 'WPINC' ) ) {
-		die;
-	}
-
-	/**
-  	 * This populates all existing UM users with meta_key `last_login` as `user_registered` if the meta key doesn't exist.
-  	 * Target Version: 1.3.39
-  	 */
-  	
-	global $wpdb, $ultimatemember;
-  	$wpdb->query('INSERT INTO '.$wpdb->usermeta.'(user_id, meta_key, meta_value) 
-	   			SELECT uu.ID, "_um_last_login", uu.user_registered
-	   				FROM '.$wpdb->users.' AS uu
-	   			WHERE 
-	   				uu.ID NOT IN(
-	   						SELECT user_id FROM '.$wpdb->usermeta.' 
-	      					WHERE meta_key = "_um_last_login" 
-	      					GROUP BY user_id
-	      			)'
-  	);
-
-
-
- ?>

admin/core/um-admin-upgrade.php

@@ -1,31 +0,0 @@
-<?php
-/**
- * This class handles all functions that changes data structures and moving files 
- */
-class UM_Upgrade {
-
-	function __construct() {
-		$um_last_version_upgrade = get_option('um_last_version_upgrade');
-
-		if( ! $um_last_version_upgrade || $um_last_version_upgrade != ultimatemember_version ){
-			add_action( 'admin_init', array($this,'packages'),10);
-		}
-		
-	}
-
-	/**
-	 * Load packages
-	 */
-	public function packages(  ){
-		
-		 $file_path = plugin_dir_path ( __FILE__ ).'packages/'.ultimatemember_version.'.php';
-		 
-		 if( file_exists( $file_path ) ){
-		 	include_once( $file_path );
-		 	update_option( 'um_last_version_upgrade', ultimatemember_version );
-		 }
-	}
-
-}
-
-new UM_Upgrade();

um-init.php

@@ -13,7 +13,6 @@ class UM_API {
 		require_once um_path . 'core/um-short-functions.php';
 
 		if (is_admin()) {
-			require_once um_path . 'admin/core/um-admin-upgrade.php';
 			require_once um_path . 'admin/um-admin-init.php';
 		}