0015506: Add register IMAGE_NUM_CURRENT

Before tt_news 3.0 i was using plugin.tt_news.imageMarkerFunc to add a new register "IMAGE_NUM_CURRENT" imitating the behaviour for default rendering.

Especially for my EXT:perfectlightbox this was needed for its typolink.title-generation. That's not working anymore...

I'd like to ask for the following addition in class.tx_ttnews.php at line 2315:

if (($iC > 0 && $this->config['firstImageIsPreview']) || ($iC >= 0 && $this->config['forceFirstImageIsPreview'])) {
$GLOBALS['TSFE']->register['IMAGE_NUM_CURRENT'] = $cc+1;
} else {
$GLOBALS['TSFE']->register['IMAGE_NUM_CURRENT'] = $cc;
}

I think this could prove useful on other occasions as well!

Best regards, Ben