uc_order requires uc_product dependency

Not major as it doesn't affect most sites; I imagine over 99% of Ubercart installs have both uc_product and uc_order enabled anyway.

I actually just bumped into this yesterday setting up a fresh dev site. Patch attached.

I guess another question that should be asked is: should these modules be dependent? Should we fix this another way? Is there a use case for having uc_order installed without uc_product?

Hm, well, I can see a use case for uc_product without uc_order (e.g. maintaining an online catalog for a brick-and-mortar store), but not really the reverse -- what would you order? I guess you could have some other custom module that took the place of uc_product, but order_products are pretty closely linked to product nodes, so it would be tricky to make that work.

@Xano: I didn't say I wasn't going to fix it; I was just asking whether the dependency is the correct solution or just the easiest one.

Committed #3.

I think it's an expedient solution, but not the right thing to do in the long run. Concepts like price and address, among others, are used by more than one sub-module, so they shouldn't be part of any one sub-module. In particular, price should be on its own, not bundled into product. However, that's a bigger change than we can make in a minor release.