Preventing Sleep on Mavericks

> Replace "pmset noidle" by "caffeinate -s" in
> Slim::Plugin::PreventStandby::OSX::new()

Thanks! I've committed a change which would use this method on systems
which support it (10.8+), falling back to pmset on the others. Could you
please give tomorrow's builds a try (7.7.4 & 7.8)?

--

Michael