Correct time formatting for Expires field added by Obj.Delete() and a…

…dd field for MaxAge=0. (#24)

get values and stamp of duplicate names cookies

update the comment of GetValueAndStamp

write retract as a range and comment it

fix test of session cookies

add package name in front of Lax

remove accessor method Key

add MustGenerateRandomKey function

change status to stable

change status to stable