New home for the repository conversion

[Joerg Sonnenberger <joerg%bec.de@localhost>]

Hello all,
the repository conversion setup for NetBSD CVS -> Fossil -> Git
has found a new home. Ironically, on former cvs.NetBSD.org hardware.
This provides a somewhat faster conversion cycle as well as removing
anoncvs.NetBSD.org from the process. This should avoid occassional
problems with incomplete syncs. Two other changes have been applied at
the same time:

- The Fossil repositories have moved to using the SHA512 checksums
  internally. To avoid accidents, a new project code is used. This
  requires Fossil 2.x.

- The Git repositories map user names to @NetBSD.org addresses
  (src, xsrc) or @pkgsrc.org addresses (pkgsrc). This allows
  consolidation on github with user accounts, assuming you have the
  corressponding addresses as primary or secondary address.

The new locations for the repositories are:
CVS    | Fossil                           | Git
-------+----------------------------------+---------------------------------
src    | https://src.fossil.NetBSD.org    | https://github.com/NetBSD/src
pkgsrc | https://pkgsrc.fossil.NetBSD.org | https://github.com/NetBSD/pkgsrc
xsrc   | https://xsrc.fossil.NetBSD.org   | https://github.com/NetBSD/xsrc

The old conversions will be provided for the near future, but likely
stop toward the end of the month.

A special thanks goes to Petra and Christos from the admin team for the
assistance with the machine setup and low-level CVS clean-ups.

Joerg