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.

2013/birken/README.md

@@ -10,7 +10,6 @@ see the [original code](#original-code) section.
 
 ## To use:
 
-
 ```sh
 ./birken.alt < 17_columns_wide_paint_by_numbers_file
 ```
@@ -65,7 +64,6 @@ hard to see the art of the entry but you may do so if you wish.
 
 ### Original build:
 
-
 ```sh
 make all
 ```