[pypy-dev] mechanism for keeping track of the latest revision on default that is known to translate

[Ronny Pfannschmidt]

since sprints regularly cause situations where default doesn't translate,
it seems helpful to have a known latest revision that translates

the proposed mechanism would be to have a bookmark
that tracks that version for default,

a good name could be something like "last-known-translatable"

that version would be a good bet for starting new branches,
since its known to translate

i'm not too sure yet how to integrate in the buildbot

regards,
Ronny