add eris-1.3.13 to the build root

[Wart]

I need to rebuild sear with the latest eris package, but eris can't be
pushed to the updates repo yet because the current sear package depends
on the old package.

Can someone from releng put eris-1.3.13 temporarily in the build root so
that I can rebuild sear and push both the updated eris and sear at the
same time?

Thanks,

--Wart