store color in world map.

js/pixl/index.html

		}
		pixl.draw_pixl = function(pos, color) {
			pixl.ctx.fillStyle = color || "black";
			var color = color || "black";
			pixl.ctx.fillStyle = color;
			var screen_pos = pixl.to_screen(pos);
			pixl.ctx.fillRect(screen_pos.x, screen_pos.y, pixl.size, pixl.size);
			pixl.world[pos.x + "," + pos.y] = {};
			pixl.world[pos.x + "," + pos.y] = {color: color};
			if (pixl.online && !pos.remote) {
				pixl.ws.send(JSON.stringify([{x: pos.x, y: pos.y, color: color || "black"}]));
				pixl.ws.send(JSON.stringify([{x: pos.x, y: pos.y, color: color}]));
			}
		}