Fix menu and various other fixes

The menu in all html pages for the FAQ was fixed to link to the step 0
(of how to enter the contest) and also it was renamed ('Enter the
IOCCC').

I also went through the most important sections of the FAQ (how to
enter and the mkiocccentry related questions) and checked the
register.html, pw-change.html and submit.html pages. It is possible I
have missed something but I think it's in pretty good shape nonetheless.

markdown.md

@@ -7,7 +7,7 @@
 </div>
 
 <p class="leftbar">
-These [IOCCC markdown guidelines](markdown.html) are version **28.0 2024-10-25**.
+These [IOCCC markdown guidelines](markdown.html) are version **28.1 2024-12-27**.
 </p>
 
 **IMPORTANT**: Be sure to read the [IOCCC rules](next/rules.html) and [IOCCC
@@ -692,3 +692,7 @@ or:
 ``` <!---markdown-->
      _**this text is bold italic**_
 ```
+
+**BTW**: the astute reader might notice that some cases of `*` for italic might
+have slipped through. We do ask you, however, to please observe this rule, as
+best you can.