The following named revisions have been set up

    Base3-10e        Unported version 3.10e
    Base3-11beta     Unported version 3.11 (beta)
    Arc3-10e         Archimedes port of version 3.10e
    Arc3-11beta      Archimedes port of version 3.11 (beta)

The base 3.11 (beta) revision is a branch off the base 3.10e revision. All
of the rest are on the main branch.

Note that only files used in the Archimedes ports have Arc... revisions.
So doing a "co -rArc..." will only get the archimedes files.
