Fix tmp/format-headers.sh, format headers

The script had "s surrounding the git ls-files command which turned it
to a single file which of course is wrong.

Ran script again fixing many README.md files that had incorrect number
of blank lines for critical headers.

This will have to be done a final but a good number of files have been
corrected.

1992/imc/README.md

@@ -29,7 +29,6 @@ cause problems for some systems where `exit(3)` returns a void.  The file
 declared argc to be a `long` which was fixed.
 
 
-
 ## Author's remarks:
 
 ### Portability