only pretend to not support IN/OUTPUT enumeration in exclusive-caps mode

if exclusive_caps are turned off, we retain the original behaviour
(which is needed for broken clients like gstreamer-0.10)

github.com Closes: umlaeute/v4l2loopback#65
set indentation to "linux" (on emacs)

setting the indentation mode via a modline is in direct violation
of the linux kernel CodingStyle
(https://www.kernel.org/doc/Documentation/CodingStyle).

we do it nevertheless :-)
(obviously the modline has to be removed if this is ever accepted into
the kernel)
updated copyright