Support for lightbox2

Hi,

First of all, thanks a lot for your plugin, I have used it in [my site](http://www.garron.me/pictures/) 

I have inserted a very small change, to support [Lightbox2](http://lokeshdhakar.com/projects/lightbox2/) so you can browse a gallery easily.

Hope you like it.

Thanks again.

Happy 2013.

Guillermo.