Empty captions are displayed

When caption is "", nivo-slider still shows it, so in bottom slider have a black line.
I fixed it by this: Change line 65-75 of sliders.inc to:

$caption = check_markup($settings['description']['value'], $settings['description']['format']);
		if ($caption != '') {
			// Generate a unique anchor to reference the HTML caption
			$description = '#htmlcaption-' . $slide;
		
			// Create the HTML caption markup
			$html_caption = '';
			$html_caption .= '<div id="htmlcaption-' . $slide . '" class="nivo-html-caption">';
			$html_caption .= check_markup($settings['description']['value'], $settings['description']['format']);
			$html_caption .= '</div>';

			// Add the HTML caption markup
			$description_html .= $html_caption;
		}