Add AsyncIterator Support

[developerworks]

All tests passed in the fork. please test again.

[developerworks]

RabbitMqConnectionFactory will caused create many connections,queues like above

[developerworks]

Connetion is reused, but created many queues every time connect to rabbitmq

[cdmbase]

@developerworks thanks for the PR. I will push your changes.

[groundmuffin]

Is it graphql-js v. ^0.11.0 compatible? The new subscribe method returns Promise that resolves to AsyncIterator. #918

[cdmbase]

it is using graphql@^0.10.5

[developerworks]

@groundmuffin The issue is caused by subscriptions-transport-ws, i think you could be waiting subscriptions-transport-ws to repair this issue apollographql/subscriptions-transport-ws#269, in my project, i've downgrade to graphql@^0.10.5