When annex.freezecontent-command or annex.thawcontent-command is configured
but fails, prevent initialization.
This allows the user to fix their configuration and avoid crippled
filesystem detection entering an adjusted unlocked branch unexpectedly,
when they had been relying on the hooks working around their filesystems's
infelicities.
In the case of git-remote-annex, a failure of these hooks is taken to mean
the filesystem may be crippled, so it deletes the bundles objects and
avoids initialization. That might mean extra work, but only in this edge
case where the hook is misconfigured. And it keeps the command working
for cloning even despite the misconfiguration.
Sponsored-by: the NIH-funded NICEMAN (ReproNim TR&D3) project
bff089a392