drop execute bit on non-executable files

* Dropped the execute bit on files which are not executable.

Require-notes: no
Require-book: no

Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>
Merge pull request #70 from calestyo/remove-execute-bits

drop execute bit on non-executable files

Acked-by: Gerd Behrmann <behrmann@nordu.net>