[CMDLINE] Add 'rm' command

[ysb33r]

Add UNIX-like rm functionality.

      -f, --force
              ignore nonexistent files and arguments, never prompt

       -i     prompt before every removal

       -I     prompt once before removing more than three files,  or  when  removing
              recursively.   Less  intrusive  than -i, while still giving protection
              against most mistakes

       --interactive[=WHEN]
              prompt according to WHEN: never, once (-I), or always  (-i).   Without
              WHEN, prompt always

       --one-file-system
              when removing a hierarchy recursively, skip any directory that is on a
              file system different from that  of  the  corresponding  command  line
              argument

       --no-preserve-root
              do not treat '/' specially

       --preserve-root
              do not remove '/' (default)

       -r, -R, --recursive
              remove directories and their contents recursively
       -d, --dir
              remove empty directories

       -v, --verbose
              explain what is being done

       --help display this help and exit

       --version
              output version information and exit

       By  default,  rm does not remove directories.  Use the --recursive (-r or -R)
       option to remove each listed directory, too, along with all of its contents.

       To remove a file whose name starts with a '-', for example '-foo', use one of
       these commands:

              rm -- -foo

              rm ./-foo