A very poor (but better than nothing) inventory icon for fences

src/mapnode.cpp

@@ -224,6 +224,7 @@ void init_mapnode()
 	f->dug_item = std::string("MaterialItem ")+itos(i)+" 1";
 	f->solidness = 0; // drawn separately, makes no faces
 	f->air_equivalent = true; // grass grows underneath
+	f->setInventoryTexture("item_fence.png");
 
 	// Deprecated
 	i = CONTENT_COALSTONE;