Typo fix in thanks file

When moving honour roll to the end of the file some things that refer to
'below' have to be changed to 'above'. It's possible more need to be
found but I've not looked at it yet. I haven't actually gone through the
file (that can come later); I just had the file open in GitHub and my
eyes zoomed in on the error.

thanks-for-help.md

@@ -4527,7 +4527,7 @@ compilers. See the README.md for more details.
 ## <a name="makefile_improvements"></a>Makefile improvements
 
 [Cody](#cody) made a variety of changes in all Makefiles, sometimes to get an entry to
-work, all noted below, but he also **improved them all** in at least one or two
+work, all noted above, but he also **improved them all** in at least one or two
 ways.
 
 For instance he changed the `LIBS` variable to `LDFLAGS` as that is the standard