Reported by the new script 'scripts/copyright.pl'. The script has a
regex whitelist for the files that don't need copyright headers.
Removed three (mostly usesless) README files from docs/
Closes#5141
Groff / Troff will display a:
printaf("Errno: %ld\n", error);
as:
printf("Errno: %ld0, error);
when a "\n" is not escaped. Use "\\n" instead.
Closes#3246
