Add msgpack and msgpack_numpy as a dependency

[spMohanty]

The evaluation service related code has a dependency on msgpack and msgpack_numpy (reference : https://github.com/stanfordnmbl/osim-rl/blob/master/osim/redis/service.py#L7) which should be added as a dependency in setup.py

We should also probably make a release after adding the same, as many submissions are failing because of lack of msgpack and msgpack_numpy