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/cable3/README.md

@@ -78,7 +78,6 @@ Update: This entry now has its own website:
 
 ## Author's remarks:
 
-
 ### A tiny but highly functional PC emulator/virtual machine
 
 The author hereby presents, for the delectation (?) of the judges, a portable PC