Unused class method: load has been deleted
Removed "load" method
Unused instance method: r() has been deleted
Delete test case codes for unused method r()
Improved codes around "stage" property
Add test case for data() method
Haineko does not contain the value of "stage" property in JSON response
Set SMTP session status value for future release
HTTP error response (such as 4xx, 5xx) is returned as a JSON without queueid
Delete test code for checking the value of "stage"