Adds dual-port vent pump. (#4270)

* Adds dual-port vent pump.

* stop being lazy and do the flag check manually

* disable vent pump behavior

Resources/Prototypes/Entities/Constructible/Piping/Atmospherics/binary.yml

@@ -125,3 +125,27 @@
           !type:PortPipeNode
           nodeGroupID: Pipe
           pipeDirection: South
+
+- type: entity
+  parent: GasUnaryBase
+  id: GasDualPortVentPump
+  name: dual-port air vent
+  description: Has a valve and a pump attached to it. There are two ports.
+  placement:
+    mode: SnapgridCenter
+  components:
+    - type: Sprite
+      netsync: false
+      sprite: Constructible/Atmos/vent.rsi
+      layers:
+        - sprite: Constructible/Atmos/pipe.rsi
+          state: pipeStraight
+          map: [ "enum.PipeColorVisualizer+Layers.Pipe" ]
+        - state: vent_off
+          map: ["enum.VentVisualLayers.Vent"]
+    - type: Appearance
+      visuals:
+        - type: PipeConnectorVisualizer
+        - type: PipeColorVisualizer
+        - type: VentPumpVisualizer
+    - type: GasVentPump