mailmap: added Wonguk Jeong's information.
mailmap: added Wonguk Jeong's information.

FlorentRevest/Elementary,FlorentRevest/Elementary,tasn/elementary,tasn/elementary,tasn/elementary,tasn/elementary,tasn/elementary,rvandegrift/elementary,rvandegrift/elementary,FlorentRevest/Elementary,rvandegrift/elementary,FlorentRevest/Elementary,rvandegrift/elementary