checkTimeoutProvokingConflicts:  These shouldn't start a server; setup
already did.  Starting two servers caused intermittent failures on
Windows, due to lockfile contention.

+ If a storage times out between the vote and the finish, the ZEO cache
  could get populated with objects that don't make it to the storage
  server.

  A new flag self._midtxn_disconnect gets reset in tpc_begin() and set
  in notifyDisconnected().  If tpc_finish() discovers this flag set, it
  raises a ClientDisconnected error before calling tpc_finish() on the
  server.

+ In tpc_finish() we re-order the calls so that the server's tpc_finish()
  is called (and must succeed) before we update the ZEO client cache.

+ The storage name is now prepended to the sort key, to ensure a
  unique global sort order if storages are named uniquely.

+ Added new tests for the above (checkTimeoutAfterVote,
  checkTimeoutProvokingConflicts, checkSortKey).

Changes:

 - startup log handler now pays attention to the logging levels of
   the handlers defined within the config file and uses the "lowest"
   level to log messages to stdout during startup.

 - entirely removed warning when the starting user's umask is "too
   permissive".  it wasn't clear that it added any value under normal
   operations.

 - replaced ancient setuid code with code stolen from zdaemon that
   works the same but looks nicer.

Don't try to optimize by checking for disabled and effective levels within the log method.  The logger's level may not be meaningful if this logger is configured with handlers that accept messages at a lower level than that of the logger itself.

usage, python2.1 fixes, and fix one or two bugs (missing import, lacking
check for invalid database type, etc)

  - Make ZEO server actually startable.  Note that the ZConfig option
    for the authentication database is named 'database', while the
    equivalent argument to the StorageServer initializer is called
    'filename':  "One of these things just doesn't belong!"

provide more than one ZConfig schema component.

from Python 2.3.
These warnings are displayed when running the unit tests.
This patch fixes the occurrances that are triggered by the unit tests;
there are probably others.

had to create a new timestamp.  Fixed.

check2ZODBThreads(), check7ZODBThreads():  Close the database when
these tests end.  Else they leak bigtime, obscuring searches for real
leaks.

Fred's machine, due to this routine falling off the end and returning
None.  Sync'ing the connection after a ConflictError appears to fix
it, or at least make it much less likely to fail.

not enough stuff in the Windows Python to wait for spawned servers to shut
down.  Spawned servers inherit descriptors for open files from the
spawning process, and because Windows won't let you delete a file that's
still open, the client can't get rid of temp .zec files until the server(s)
disappear(s).  There's no good fix for this before 2.3 on Windows.  For
now, try deleting the temp files repeatedly, sleeping between failures,
but don't wait forever.  If a temp file can't be deleted in the end, raise
the appropriate exception.  This should be rare.  It's important not to
keep going blindly, as I saw one case earlier today where a test passed
by accident due to picking up a .zec file left behind by a previous test
run.

it actually manages to do a commit on the second server.

too.  Mystery:  whether this test dies with permission denied when
trying to unlink the .zec file is still a crapshoot.   Don't know why.
At least four other tests show sporadic failures of the same kind.

Otherwise the temp zec file can't be deleted on Windows.

zec file name (the code intended to do this all along).