Add auth0 source function

[spencerattick]

Hey folks! Success Eng has received several tickets in the past couple of weeks related to logs from a tool called Auth0 and how those events can be pulled into Segment. The data that Auth0 sends out as logs doesn't follow the format Segment's ingestion API expects. As such, payloads can be dropped or data is not passed in its entirety to warehouses and/or other destinations where customers would like to use it.

Auth0 has deprecated their integration with Segment and all other third-party extensions but they have an option to send logs downstream via webhook. As such, I've written a quick Source Function to help customers more easily send Auth0 logs to Segment.