LoadedTurrets by CaveGrinder almost completely rewritten for 0.18.

Creates a new item and recipe to load a turret with ammunition for each valid combination of turret and ammo.

When placed, creates a turret with ammo loaded into it.

Recipes are unlocked when both turret and ammo are available.

Not compatible with the original mod, as it uses a different naming scheme for the new items, but should be more compatible in future.