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.

1998/bas2/README.md

@@ -13,7 +13,7 @@ echo text | ./bas2
 ```
 
 
-## Try:
+### Try:
 
 ```sh
 ./try.sh
@@ -24,7 +24,6 @@ echo text | ./bas2
 
 ## Judges' remarks:
 
-
 ### Questions to ponder:
 
 Can you determine the relationship between the input and the resulting numeric