bug#7784: executable-find does not find scripts on woe32

[Óscar Fuentes]

Sam Steingold <sds@gnu.org> writes:

> (file-executable-p "c:/gnu/cygwin/bin/bzr")
> ==> nil
> which is wrong because bzr is an executable python script.

How does Emacs know that bzr is a Python script? Because it has

#!/usr/bin/python

as the first line? That only makes sense within the Cygwin environment,
i.e. if you are running a Cygwin-based Emacs.

As you know, there is no 'executable' attribute on Windows. Cygwin fakes
it.