[tex-live] Please default \pdftrailerid{} to SOURCE_DATE_EPOCH if exported

[Karl Berry]

      -/ID [<A979E943C51DC1AAE48AAFF27BBA5A0D> <EA2B7DBF37C8E3DC2AA0AFDAA1FF4E0C>]
      +/ID [<EA2B7DBF37C8E3DC2AA0AFDAA1FF4E0C> <A979E943C51DC1AAE48AAFF27BBA5A0D>]

    This varies depending on the *path* from which you are building,

Ack, thanks for the report.

I'll send a patch after I have a chance to construct one, if no one else
(Akira?) gets there first.  --thanks, karl.