test_case: car_is_not_parked_when_create
move park_test.cc to test directory
add gitignore file
test case: park_car_is_not_changed_after_park_pick
test case:car_is_not_parked_after_pick_car
test case:park_free_count_is_not_changed_after_park_pick
park_create_throw_exception_when_capacity_is_not_valid