fixes regression with backwards compatibility to allow 'session' key in options arg for generateToken
fixes regression with backwards compatibility to allow 'session' key in options arg for generateToken

aoberoi/opentok-node,AntonioMA/opentok-node,davemun/opentok-node,opentok/opentok-node,bsstoner/opentok,hbaqai/opentok-node,jeffswartz/opentok-node