Separate part management from the rest of body manager component (#2017)

* Separate part management from the rest of body manager component

* Component reference

* Move more methods over

* Fix docs and move over BodyPreset

* Fix up body preset

* Create initialize method and remove constructor for BodyPreset

* Do the same for BodyTemplate and add Initialized properties

* Fix BodyTemplate HashCode test

* BodyTemplate test PLS

Content.Server/Body/BodyCommands.cs

@@ -93,7 +93,7 @@ namespace Content.Server.Body
             }
             else
             {
-                body.DisconnectBodyPart(hand.Value, true);
+                body.RemovePart(hand.Value, true);
             }
         }
     }