Add night view via ambientlight setting on Flat and Surface maps, add

night-and-day setting to generate both night (default) and day
(prefix+'_day') versions of tiles, and add transparency to generated
PNG files

src/main/java/org/dynmap/kzedmap/KzedMapTile.java

@@ -26,6 +26,11 @@ public class KzedMapTile extends MapTile {
         return renderer.getName() + "_" + px + "_" + py + ".png";
     }
 
+    @Override
+    public String getDayFilename() {
+        return renderer.getName() + "_day_" + px + "_" + py + ".png";
+    }
+
     @Override
     public int hashCode() {
         return getFilename().hashCode() ^ getWorld().hashCode();