2018/ferguson fixes and minor updates

Fix test.sh for shellcheck.

Minor fixes to README.md including moving the author information (that
is my information :-) ) to the first column of the file as not having it
prevents links from being generated right. This is a problem for the
other README.md files too and I'll be noting it on GitHub.

Some humour with html <del>..</del>.

Modified portability section to make it a bit simpler and suggest that I
won't be updating the list. I only include the original systems tested
for historical purposes. I won't be updating the list over time as that
would be annoying to do and would just make the already very long
document needlessly longer. It's already been almost 5 years since it
was updated.

Add a string to test-strings.txt.

Warning: these are most likely not the final fixes or updates for my
entries as Landon has pointed out :-) but there shouldn't be many more
for now or hopefully for a long time. Unless I see something I won't
feel the need to fix anything.

Update 2018/burton2/README.md to have my middle name.

2018/burton2/README.md

@@ -381,7 +381,7 @@ cc -ansi -Wall -trigraphs -Wno-trigraphs -Wno-parentheses -Wno-empty-body -Wno-c
 
 ### Coda
 
-Cody Ferguson was relentless in his pursuit of bugs.
+[Cody Boone Ferguson](/winners.html#Cody_Boone_Ferguson) was relentless in his pursuit of bugs.
 Thanks to his reports, the version of `unob.sh` is stronger,
 `tac` groks digraphs, `tokenfix` corrects for missing digraphs in `prog.c`,
 and the program `manpage` was added to the corpus.