Feat: Rename `delete`/`remove` -> `rm`

There will be `rename` and
there should be `mv` instead of `move`.

diff --git a/delete b/rm
similarity index 100%
rename from delete
rename to rm

diff --git a/submodules/remove b/submodules/rm
similarity index 100%
rename from submodules/remove
rename to submodules/rm