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.

1993/ant/README.md

@@ -39,7 +39,7 @@ unobfuscated version provided by the author. You can look at this code if you
 want some clues in how it works.
 
 
-## Alternate build:
+### Alternate build:
 
 If you wish to build this deobfuscated version, you can do so like:
 
@@ -49,12 +49,12 @@ If you wish to build this deobfuscated version, you can do so like:
 ```
 
 
-## Alternate use:
+### Alternate use:
 
 Use `ant.alt` like you would `ant` above.
 
 
-## Alternate try:
+### Alternate try:
 
 ``` <!---sh-->
     ./try.alt.sh

1993/ant/index.html

@@ -426,12 +426,12 @@ code</a> below.</p>
 <p>The <a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/1993/ant/ant.alt.c">ant.alt.c</a> is an
 unobfuscated version provided by the author. You can look at this code if you
 want some clues in how it works.</p>
-<h2 id="alternate-build">Alternate build:</h2>
+<h3 id="alternate-build">Alternate build:</h3>
 <p>If you wish to build this deobfuscated version, you can do so like:</p>
 <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> like you would <code>ant</code> above.</p>
-<h2 id="alternate-try">Alternate try:</h2>
+<h3 id="alternate-try">Alternate try:</h3>
 <pre><code>    ./try.alt.sh</code></pre>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <p>See the author’s POSIX P1003.2-like documentation file <a href="ant.txt">ant.txt</a> for