linux standalone: Generate locale files in ~/.cache/git-annex/locales/ so
they're available even when the standalone tarball is installed in a
directory owned by root.
This avoids a full-on reference counting cleanup hell, by letting old
locale caches linger as long as the standalone bundle directory associated
with them is still around. Old ones get cleaned up.
In the case where the directory has a new bundle unpacked over top of it,
the old locale cache is invalidated and rebuilt. Of course, running
programs using that may get confused, but this was already the case, and
unpacking over top of a bundle is probably not a good idea anyhow.
To support that, added a buildid file, which only needs to be unique across
builds of git-annex with different libc versions. sha1sum of git-annex
seems good enough for that.
Removed debian/patches/standalone-no-LOCPATH as it's no longer
necessary.
This commit was supported by the NSF-funded DataLad project.
