makes conveyors to use machine linking & refactors machine linking a bit (#2464)

* makes conveyors to use machine linking & refactors machine linking a bit

* nullable errors

* temp commit, starting work on construction

* working recipies & graphs

* fixes crash

* makes items gravitate towards the center when on a conveyor

* makes conveyors take bool signal too

* ignores components clientside

* default arm
entitymanager
maxtransmitters
unsubscribe methods

* twowayLEVER

* _

* componentreference
struct

* yaml run
leverDefinitelyNotCopiedFromGirderNoNoNo dies today :(

* nullable

* no divide by 0

* making sloth happy

* space gone - happy?

* final fix

* yes

* adds item to lathe

* conveyor item -> conveyor assembly

* technology

* reviews ADRESSED

* Update Content.Shared/GameObjects/Verbs/VerbUtility.cs

Co-authored-by: Paul <ritter.paul1+git@googlemail.com>
Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>
Co-authored-by: Metal Gear Sloth <metalgearsloth@gmail.com>

Content.Shared/GameObjects/Components/MachineLinking/TwoWayLeverSignal.cs

@@ -0,0 +1,19 @@
+using System;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.GameObjects.Components.MachineLinking
+{
+    [Serializable, NetSerializable]
+    public enum TwoWayLeverVisuals : byte
+    {
+        State
+    }
+
+    [Serializable, NetSerializable]
+    public enum TwoWayLeverSignal : byte
+    {
+        Middle,
+        Left,
+        Right
+    }
+}