These are defined in ifelse, but it's not currently available and I don't
want to pull in a library for 6 lines of code anyhow.
Also, ifelse sets the fixity to 1, which does not allow >>? error $ ...
Fully tested and working, including resuming and encryption. (Though not
resuming when sending *with* encryption; gpg doesn't produce identical
output each time.)
Uses same layout as the directory special remote and the .git/annex/objects/
directory.
