INN snapshot changes

I think I have updated snapshot generation so that it will base the
snapshots on Git rather than Subversion.  I've also moved, but not gotten
rid of, the daily snapshots since there was a request to keep them.

The daily snapshots are now in a subdirectory named daily of the snapshots
directory and should continue working as before.

At the top level, there should (starting after tonight) be snapshots from
the 2.6 and main branches.  The 2.6 snapshots will use the version number
from git describe.  Since that's useless for main because of our branching
strategy, the main snapshots will still be time-based, but the version
number will be a little different (2.7-YYYYMMDD), and the date will be
that of the most recent commit.  Both should only be generated if
something changed.

If you want to keep using the snapshots as before, just update your path
to use the daily directory.

-- 
Russ Allbery ([email protected])             <https://www.eyrie.org/~eagle/>

    Please send questions to the list rather than mailing me directly.
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