Don't automatically recalculate crafting plans

Instead, any time a change is made which invalidates a crafting plan,
update the visual display to show that the plan is out of date, and
add some extra affordances to recalculate.

src/client/models/site/craft_page.coffee

@@ -40,6 +40,7 @@ module.exports = class CraftPage extends BaseModel
             inventory.each (stack)=>
                 item = @modPack.findItem stack.itemSlug, enableAsNeeded:true
                 return unless item? and item.isCraftable
+
                 @craftsman.want.add stack.itemSlug, stack.quantity
                 inventory.remove stack.itemSlug