cat --help does not work

[certik]

$ cat --help
cat: unsupported flag: --help

Compare to zsh:

$ cat --help
cat: illegal option -- -
usage: cat [-belnstuv] [file ...]

Not the best, but still better.

Even better is man cat, which works in both zsh and shell. However, the options I think are only meant for zsh's cat, not our cat.

I think for our commands, we should support --help and print a nice well documented help screen for each option. ls --help works well.