Who was the incoming head coach after Wan Jamak Wan Hassan quit the coaching job?
CREATE TABLE "coaching_changes" (
  "club" text,
  "outgoing_head_coach" text,
  "date_of_vacancy" text,
  "manner_of_departure" text,
  "incoming_head_coach" text,
  "date_of_appointment" text
);
SELECT "incoming_head_coach" FROM "coaching_changes" WHERE "outgoing_head_coach"='Wan Jamak Wan Hassan';