Added documentation git-lfs-ls-files' */- output.
Added documentation git-lfs-ls-files' */- output.

This functionality was introduced in
https://github.com/git-lfs/git-lfs/commit/2082b26ce728bb8a960b28bcac9aaecbb6a251c1.
github/git-lfs,github/git-lfs,github/git-lfs