Entity::update_connection to add fluid inputs to miners

[Mylon]

Feature request: Provide a way to add fluid boxes to a miner after placement. Either via entity::update_connection or entity.active = false ; entity.active = true

Use case: on_resource_depleted, I spawn a new resource that requires a fluid to mine. The miner stops working and must be destroyed and replaced before it will spawn the fluid boxes and allow mining again.