def create_or_update_body_weight_goal(startDate, startWeight, goalWeight)
      opts = {startDate: format_date(startDate), startWeight: startWeight, weight: goalWeight}
      post("/user/#{@user_id}/body/log/weight/goal.json", opts)
    end
def create_or_update_body_weight_goal(startDate, startWeight, goalWeight)
      opts = {startDate: format_date(startDate), startWeight: startWeight, weight: goalWeight}
      post("/user/#{@user_id}/body/log/weight/goal.json", opts)
    end
Create or update a user's weight goal

 @param [DateTime, Date, String] startDate Weight goal start date;
   in the format "yyyy-MM-dd" if a string
 @param [Decimal, Integer, String] startWeight Weight goal start weight;
   in the format "X.XX" if a string
 @param [Decimal, Integer, String] goalWeight Weight goal target weight;
   in the format "X.XX" if a string

 @since v0.9.0