Starting to reassign waiting_step in shmem_vecenv (#915)
Starting to reassign waiting_step in shmem_vecenv (#915)

"self.waiting_step" is initialized in __init__ function but it is not reassigned anywhere.
Because it is used in reset function and close_extras function, it should be fixed.
So i fixed it to be similar with subproc_vec_env's one.
openai/baselines,openai/baselines