export eventSource default getRequest and getResponse functions

[sarahgancisonos]

I recently needed to slightly modify the eventSource getRequest function but did't need to modify the getResponse function.

Could you export all of the eventSource aws getRequest & getResponse functions and helper functions such as:
getResponseToApiGateway
getRequestValuesFromApiGatewayEvent
getRequestValuesFromEvent
etc.

This would help people who want to slightly tweak the logic used for various aws events.

Thanks!