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.

1992/ant/README.md

@@ -33,14 +33,14 @@ This version, [ant.alt.c](%%REPO_URL%%/1992/ant/ant.alt.c), was provided by the
 author in 2024, and is an unobfuscated version.
 
 
-## Alternate build:
+### Alternate build:
 
 ``` <!---sh-->
     make alt
 ```
 
 
-## Alternate use:
+### Alternate use:
 
 Use `ant.alt` as you would `ant` above.
 

1992/ant/index.html

@@ -421,9 +421,9 @@ code</a> below.</p>
 <h2 id="alternate-code">Alternate code:</h2>
 <p>This version, <a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/1992/ant/ant.alt.c">ant.alt.c</a>, was provided by the
 author in 2024, and is an unobfuscated version.</p>
-<h2 id="alternate-build">Alternate build:</h2>
+<h3 id="alternate-build">Alternate build:</h3>
 <pre><code>    make alt</code></pre>
-<h2 id="alternate-use">Alternate use:</h2>
+<h3 id="alternate-use">Alternate use:</h3>
 <p>Use <code>ant.alt</code> as you would <code>ant</code> above.</p>
 <h2 id="try-1">Try:</h2>
 <pre><code>    ./try.alt.sh</code></pre>