add the ability to build flipped blueprints in LuaItemStack::build_blueprint

[ahicks]

If one wants to build from the item stack in hand via using build_from_cursor or directly via LuaItemStack, it's not possible to specify flips. We found out that this is actually only in the frontend. While mods can flip blueprints today via directly editing JSON, the various FFFs make it clear that flipping is becoming more complicated in 2.0. It'd be amazing if we could pass (say) flip_horizontal and flip_vertical, or however you want to do it. The current alternative is seemingly to export to JSON, try to edit said JSON, then import back.

Factorio Access again, wrt use case: we can't let players build flipped blueprints because that mandates the mouse. Of course with this one there's tons of uses for it beyond us.

[Gweneph]

LuaPlayer.build_from_cursor now has a mirror parameter but it doesn't seem to function for blueprints. I think making that work for blueprints would be the best way to resolve this issue for us.