bug#43153: Add new command project-find-dir (and move binding of project-dired)

[Stefan Kangas]

Severity: wishlist

Please consider adding a new command `project-find-dir' that works like
`project-find-file' but for directories.

I would also suggest to move `project-dired to `C-c p D' and put the new
`project-find-dir' command on `C-c p d'.  These key bindings would be in
line with the third-party projectile package.

Thanks in advance.