Update README

Author: ishikawa999

README.md

@@ -1,21 +1,17 @@
 # redmine_message_customize
 
 This is a plugin for Redmine.  
-This plugin changes the translation of the wording on the screen defined in "config/locales/*.yml" in the admin view.
+This plugin changes the translation of the wording on the screen defined in "config/locales/*.yml" in the admin view.  
+It is available for Redmine 6.0 or later.
 
 ## Install
 
 ```
 $ cd /your/path/redmine
 $ git clone https://github.com/farend/redmine_message_customize.git plugins/redmine_message_customize
-$ # When Redmine 4.1 or lower versions
-$ cp plugins/redmine_message_customize/35_change_load_order_locales.rb config/initializers/35_change_load_order_locales.rb
 $ # redmine restart
 ```
 
-:warning: To customize messages for other plugins in **Redmine 4.1 or lower versions**, redmine_message_customize/35_change_load_order_locales.rb It is necessary to copy the file to redmine/config/initializers.  
-If redmine/config/initializers/35_change_load_order_locales.rb is missing, only non-plugin messages can be customized.
-
 ## Usage
 
 * 1: Open setting page