Fix issues with New and Destroy in NTNet

- New() on atoms needs to call parent.
- Destroy() needs to return a qdel hint.
- Only add yourself to processing in Initialize() to make sure globals are instantiated.

code/modules/modular_computers/file_system/computer_file.dm

@@ -23,7 +23,7 @@ var/global/file_uid = 0
 	if(holder.holder2 && holder.holder2.active_program == src)
 		holder.holder2.kill_program(1)
 	holder = null
-	..()
+	return ..()
 
 // Returns independent copy of this file.
 /datum/computer_file/proc/clone(var/rename = 0)