Folders props, and adds the laser prism, receptor, and sealed doors. (#5337)

* Re-bases props, and adds the laser prism.

* Ver 1 of Puzzle Lock and Doors

* Doors

* Fix door hiccup I made, modify Prism

code/game/objects/structures/props/prop.dm

@@ -0,0 +1,18 @@
+//The base 'prop' for PoIs or other large junk.
+
+/obj/structure/prop
+	name = "something"
+	desc = "My description is broken, bug a developer."
+	icon = 'icons/obj/structures.dmi'
+	icon_state = "safe"
+	density = TRUE
+	anchored = TRUE
+	var/interaction_message = null
+
+/obj/structure/prop/attack_hand(mob/living/user) // Used to tell the player that this isn't useful for anything.
+	if(!istype(user))
+		return FALSE
+	if(!interaction_message)
+		return ..()
+	else
+		to_chat(user, interaction_message)