feature request: mount and navigare/browse filesystems

[cinghiopinghio]

Dear dev,
thanks for this nice tool.

I would like to request/suggests a mechanism to mount and navigate filesystems such those provided by fuse.

Consider zip files, at the moment I can choose the external tool to use through mimetype.toml. In this way I'm forced to visit the zipped file outside joshuto.
With fuse-zip I can mount the zip file somewhere and browse its content from within joshuto.
Of course one should handle the unmount of the fuse filesystem on exit.

A similar workflow can be used to mount remote filesystems through ssh and navigate them within joshuto (this is performed in vifm with a particular file with .ssh extension).

One could even use joshuto as an email client mounting the notmuch database through notmuchfs (this may be out of scope though ;-) ).

I couldn't reproduce this behaviour with the current state of joshuto.

bests