[dev] @include instead of include

[Chuck Hagenbuch]

Quoting steve <mailling at gmx.co.uk>:

> I don't get why we should use @include
> It happens to me, but it can happen to others, it hides errors

Because of the file maybe not being there, but since include isn't a fatal
error, and there's a config setting wrapper around both of these, I've applied
the patch. Thanks.

-chuck

--
Charles Hagenbuch, <chuck at horde.org>
"I'm really... I'm not too fascinated by green food." - Average Joe