A new service for Cachefilesd

[Felix Lechner]

Hi everyone,

A little while ago, Bruno Victal and I wrote a service for Cachefilesd
together. [1] I have been using it in production for several months.
Someone told me the bug was too old to be eligible for automatic CI
builds that might have attracted a committer's attention. In lieu of
that automatic signal, I am therefore sending this friendly reminder.

Cachefilesd is a daemon that uses the "FS-Cache" feature in the Linux
kernel [2] to improve the user experience with remote file systems
like NFS.

Kind regards
Felix Lechner

[1] https://issues.guix.gnu.org/41180#7
[2] https://www.kernel.org/doc/html/latest/filesystems/caching/fscache.html