format headers

We move `tmp/format-headers.sh` into `bin/format-headers.sh`.

We also add a few missing empty lines to `README.md`.

We add `bin/format-headers.sh` to the `bin/README.md`.

We run `bin/format-headers.sh` to perform the above.

Performed `make www` to accomplish the above and to test under macOS.

2011/toledo/index.html

@@ -415,7 +415,7 @@ controls and size</a> and <a href="https://github.com/ioccc-src/temp-test-ioccc/
 Windows</a>. See <a href="#alternate-code">Alternate code</a> below.</p>
 <h2 id="to-use">To use:</h2>
 <pre><code>    ./toledo</code></pre>
-<h2 id="alternate-code">Alternate code</h2>
+<h2 id="alternate-code">Alternate code:</h2>
 <p>The first alt version, <a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2011/toledo/toledo.alt.c">toledo.alt.c</a>, allows you to reconfigure
 the controls and the dimensions more easily.</p>
 <p>The second version, <a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/2011/toledo/toledo.alt2.c">toledo.alt2.c</a>, should work for Windows but