Result of `make doc` is confusing

[kmcallister]

make: Nothing to be done for `doc'.

That's because doc refers just to the directory of that name. The PHONY docs target is named docs.

I don't know what exactly to do about this, but it's confusing.

[duckinator]

Adding a line to the Makefile that says doc: docs will make them equivalent, if that's what's wanted.

[steveklabnik]

I think that should be fine. Let's see! Thank you!