完成发送邮件到小号，刷新小号数据库并且实时刷新窗口的功能。
--@@ TODO: solve COD item, maybe displaying COD amount above the slot icon or using tool-tip

--@@ TODO: function SortDB must clear up! collect garbage !!!
	--UC..
--@@ TODO: add searching bar!

--@@ TODO: add AH ordering
	--UC..bad to do
--@@ TODO: should stacked attachments can be collect??

--@@ TODO: collect mailbox gold??
	--DONE!
--@@ TODO: should attachments info be saved to database when sending to known player's other characters?
	--DONE!
--@@ TODO: should attachments be alerted to player to collect when almost in deadline?

--@@ TODO: localization!