[texdoc] Some small bugs and more

[Karl Berry]

Hi Patrick - thanks for the ideas. My reactions are:

1. Certainly making documentation on LaTeX commands more easily
accessible would be a good thing.

2. As others have written, and as I wrote in my earlier reply,
  http://tug.org/pipermail/texdoc/2017q4/000412.html
I don't think texdoc is the place to do it. texdoc is about finding
documents, not looking inside documents. Two totally different things.
texdoc is not Google and can't be everything to all people.

3. The latex2e.texi (.html,.info,.pdf,...) document already has a
"keyword list" -- the index(es).  A separate program that accesses
latex2e with some heuristic cmdline parsing sounds like a good idea to me.

FWIW, standalone Info already has basic functionality:
  info --index-search=enumerate latex2e
(I haven't actually run this, but I hope it comes up with something.)

But of course most people don't like Info (or won't have latex2e.info
installed and available), so that's not a general solution.  (BTW,
perhaps I should combine the Concept and Command indexes in the
document; I've gone back and forth in my mind on that ...)

4. latex2e.texi is a reference manual, not a tutorial, so the emphasis
on "newbies" is misplaced. Some kinds of newbies do indeed want "just
the facts", and for them it will work fine. Other people (quite
reasonably) want everything spelled out, and latex2e.texi won't do
that. It can't be everything to all people either.

5. latex2e.texi is quite noticeably incomplete. More help with writing
(good!) descriptions of commands would be wonderful. I doubt I will
finish it in this lifetime ... --all the best, karl.