joyent/node-http-signature — pull request #5 by geebee (2012-09-08 15:44:52+00:00)
Title: If x-date is available, discard date and continue parsing the authorization with x-date

Hey Mark,

I went for the simplest possible solution, and I think it fits, and meets your requirements.

Basically, If `x-date` is an available header, discard `date` and continue signing with `x-date` (by setting the value of the `date` header to the value of the `x-date` header).

In this way, all of the other default options and parsing logic require no modification, and, if the `date` header is passed without the `x-date` header, all will be exactly as it was. If both are passed, `x-date` will take priority.