Beds: priv/griefing fixes.

- disallow placing beds in protected areas
- fix rotation of beds(broken after 41c2b2ae)
- allow using others' beds, but don't change spawn location

Fixes #953. #943 isn't something I think was ever implemented, and
this does a fair job of addressing the main concern (spawning in
others' houses)

mods/beds/spawns.lua

@@ -18,8 +18,8 @@ function beds.read_spawns()
 		repeat
 			local x = input:read("*n")
 			if x == nil then
-            			break
-            		end
+				break
+			end
 			local y = input:read("*n")
 			local z = input:read("*n")
 			local name = input:read("*l")
@@ -52,7 +52,10 @@ function beds.set_spawns()
 	for name,_ in pairs(beds.player) do
 		local player = minetest.get_player_by_name(name)
 		local p = player:getpos()
-		beds.spawn[name] = p
+		-- but don't change spawn location if borrowing a bed
+		if not minetest.is_protected(p, name) then
+			beds.spawn[name] = p
+		end
 	end
 	beds.save_spawns()
 end