add unsubscribe() method for the Subscription instance to allow to unsubscribe the Subscription directly without using the RxPubSub's unsubscribe method
add unsubscribe() method for the Subscription instance to allow to unsubscribe the Subscription directly without using the RxPubSub's unsubscribe method

t0w5a/rx-pubsub,t0w5a/rx-pubsub,t0w5a/rx-pubsub