Add RequestIDFilter

Added a filter which drops the automatic addition of user information to logs and simply adds the request id.

This was necessary for us because we have a custom user that delays fetching of user information until needed, and when peavy attempted to add the user information to the log output we were getting recursion errors related to the logging done while fetching that information. 

Sharing this small change in case you find it would be useful for peavy users at large.