remove manager postfixes

inc/map/map.manager.lua

@@ -1,6 +1,6 @@
 local _maps = {}
 
-function MapManager.get_maps_array()
+function Map.get_maps_array()
   local maps_array = {}
   for _, map_data in pairs(_maps) do
     table.insert(maps_array, map_data)
@@ -8,19 +8,19 @@ function MapManager.get_maps_array()
   return maps_array
 end
 
-function MapManager.register(map_data)
+function Map.register(map_data)
   if _maps[map_data.id] then
     trace("Warning: Overwriting map with id: " .. map_data.id)
   end
   _maps[map_data.id] = map_data
 end
 
-function MapManager.get_by_id(map_id)
+function Map.get_by_id(map_id)
   return _maps[map_id]
 end
 
-function MapManager.draw(map_id)
-  local map_data = MapManager.get_by_id(map_id)
+function Map.draw(map_id)
+  local map_data = Map.get_by_id(map_id)
   if not map_data then
     return
   end