Not including such remotes turned out to have other consequences,
including annex-truselevel git config being ignored. Instead, add guards
before each operation that might try to operate on such a repo.
Prelude.undefined error message was introduced by
bb4f31a0ee.
It seems best to filter out local repositories that cannot be accessed
from the list of remotes, rather than keeping them in and making every
thing that uses the list have to deal with remotes that may have an unknown
location.
Besides fixing the error message, this also makes unavailable local
remotes' names not be shown in various messages, including in git annex
status output.
Also, move --to an unavailable local repository now avoids some ugly
errors like "changeWorkingDirectory: does not exist".
It's possible for there to be multiple queued changes all adding the same
file, and for those changes to be reordered. Maybe. This check will guard
against that ending up adding the wrong version of the file last.
Rethought how to keep track of pending adds that need to be retried later.
The commit thread already run up every second when there are changes,
so let's keep pending adds queued as changes until they're safe to add.
Also, the committer is now smarter about avoiding empty commits when
all the adds are currently unsafe, or in the rare case that an add event
for a symlink is not received in time. It may avoid them entirely.
This seems to work as before for inotify, and is untested for kqueue.
(Actually commit batching seems to be improved for inotify, although I'm
not sure why. I'm seeing only two commits made during large batch
operations, and the first of those is the non-batch mode commit.)
