Improve menu and link title and consistency

A few page names were changed and menu link (titles) were changed too.
By page names it means either DESCRIPTION or HEADER_2 in
bin/md2html.cfg. Although it looks better and is more consistent, there
might be one or two that can be further improved.

Naturally every html file that is markdown based was updated.

next/README.md

@@ -1,4 +1,4 @@
-# IOCCC Rules and Guidelines
+# Rules and Guidelines
 
 **IMPORTANT**: Did you read the **Important disclaimers about scope**
 and did you check the current **[IOCCC status](../status.html)**?