add next/submit.html and improve FAQ and other refs to entering the IOCCC

Added a new `next/submit.html` to move the "how to submit" form "in-line"
of the top FAQ entry into a new page managed by `next/submit.md`.
Thus, `next/submit.html` is a parallel to `next/register.html`
and `next/submit.md` is a parallel to `next/register.md`.

Changed the FAQ "faq.html#submit" and into "faq.html#enter".

Added individual tags for the steps in FAQ0.0.

Moved "faq.html#register" down to FAQ 0.0 step 2.

Added "faq.html#submit" for FAQ 0.0 step 5,
however elsewhere often "next/submit.html" is used.

Changed references for "faq.html#upload" to "next/submit.html".

We made a number of changes to the following markdown files to reflect the above:

- `about.md`
- `faq.md`
- `index.md`
- `markdown.md`
- `next/README.md`
- `next/README.md`
- `next/guidelines.md`
- `next/register.md`
- `next/rules.md`
- `nojs-menu.md`
- `status.md`

as well as these files:

- `bin/gen-top-html.sh`
- `bin/md2html.cfg`

and added:

- `next/submit.html`
- `next/submit.md`

Perform `make www` and `make gen_status` to perform the above and test under macOS.

TODO: Add images about the mailing list to `next/register.md`.  See the line:

```
XXX - **put images and other details about joining the mailing list here** - XXX
```

next/guidelines.html

@@ -514,10 +514,7 @@ The submit URL should be active on or slightly before <strong>2024-MMM-DD HH:MM:
 The <a href="rules.html">IOCCC rules</a> and these <a href="guidelines.html">IOCCC
 guidelines</a> will be available on the <a href="https://www.ioccc.org">Official IOCCC
 website</a> on or slightly before start of this IOCCC. Please check our
-FAQ on “<a href="../faq.html#submit">how to submit</a>”
-to see how to submit entries, on or after the start of this IOCCC, to be sure
-you are using the correct versions of these items before using the
-IOCCC submission URL.
+page on how to <a href="submit.html">upload your submission</a> when the contest is <a href="../status.html#open">open</a>.
 </p>
 <p class="leftbar">
 The <a href="rules.html#rule2a">Rule 2a</a> size has <strong>increased from 4096 to 4993</strong> bytes.