[racket] info.rkt `deps` (was: Package fails to compile during 'make in-place' but not 'raco pkg install')

To loop back on this:

I updated the info.rkt for all my packages.

I also submitted PRs or requests for a couple packages I depend on,
which were missing this.  Because one consequence of this idea...

> So: In my .travis.yml files I already run `raco pkg install`. What I
> think I will do is also run `raco setup` to look for undeclared
> dependencies.
>
> That way I'll be alerted if the deps are wrong for a new package, or
> after changing an existing one, or even for pull requests from other
> folks (since Travis automatically runs on PRs, too).

...is that it will error for _any_ package missing deps. Not just
mine, but could be one on which I depend.

Is it "too harsh that, even if my stuff is OK, Travis could say "build
failed"? No, I think it's good. If I depend on another package, then I
accept the responsibility of making sure it's, um, dependable.
Otherwise I shouldn't use it. The buck^H^H^H^H bitcoin stops here.