This patch adds a technology that allows ranged units to aim at moving targets (something they currently do by default). Without the technology now they'll instead aim at where the target is standing, so against moving targets they'll be much less accurate.
I'm actually not convinced this is a good idea, but I thought I should upload the patch anyway and see what others think.
(Currently buildings don't have the Ranged class, so I added that to make it easier to apply the technology. A consequence of this is that "Will to Fight" now applies to those buildings as well, which I think is the correct behavior, since the garrisoned units are adding arrows. But it's easy to fix that if it's unwanted.)