#1055 Remove multiple "please register" messages

Part 1:
- Use only one message entry for "Please register", that may have to be adapted to reflect the proper /register arguments
- Remove other message entries from code and from the messages files

Breaking change: reg_email_msg is also removed

src/main/resources/messages/messages_zhhk.yml

@@ -21,7 +21,6 @@ no_perm: '&8[&6用戶系統&8] &b嗯～你想幹甚麼？'
 error: '&8[&6用戶系統&8] &f發生錯誤，請與管理員聯絡。'
 login_msg: '&8[&6用戶系統&8] &c請使用這個指令來登入： 《 /login <密碼> 》'
 reg_msg: '&8[&6用戶系統&8] &c請使用這個指令來註冊： 《 /register <密碼> <重覆密碼> 》'
-reg_email_msg: '&8[&6用戶系統&8] &c請使用這個指令來註冊： 《 /register <電郵> <重覆電郵> 》'
 usage_unreg: '&8[&6用戶系統&8] &f用法： 《 /unregister <密碼> 》'
 pwd_changed: '&8[&6用戶系統&8] &c你成功更換了你的密碼 ！'
 user_unknown: '&8[&6用戶系統&8] &c此用戶名沒有已登記資料。'
@@ -68,9 +67,6 @@ invalid_name_case: '&8[&6用戶系統&8] &4警告！&c你應該使用「%valid
 # TODO denied_command: '&cIn order to use this command you must be authenticated!'
 # TODO same_ip_online: 'A player with the same IP is already in game!'
 # TODO denied_chat: '&cIn order to chat you must be authenticated!'
-# TODO reg_no_repeat_msg: '&3Please, register to the server with the command "/register <password>"'
-# TODO reg_email_no_repeat_msg: '&3Please, register to the server with the command "/register <email>"'
-# TODO reg_psw_email_msg: '&3Please, register to the server with the command "/register <password> <email>"'
 # TODO password_error_chars: '&4Your password contains illegal characters. Allowed chars: REG_EX'
 # TODO email_show: '&2Your current email address is: &f%email'
 # TODO show_no_email: '&2You currently don''t have email address associated with this account.'