update readme
Add *http.Request to Session struct allowing you to inspect the initial ajax request
Merge pull request #34 from Sean-Der/0.9.x

Add *http.Request to Session struct allowing you to inspect the initial ajax request
Add support for acknowledgement functions, if an event packet has an ack last argument becomes a callback
Move ackCallback generation into its own named function
Finish acknowledgement function implementation, if the event packet requests an ack and the handler doesn't have one make sure to add one to callArgs so we will get an error from .Call
Merge pull request #36 from Sean-Der/0.9.x

Implemented Acknowledgment Callback