Nitrogen module fix makes SlideBlast working correctly in IE7.

I recently reported on a successful SlideBlast presentation server setup. Unfortunately, it worked well only on Firefox and Safari, not on the Internet Explorer. The Z-order is treated differently in the Microsoft browser line than e.g. in Firefox. To make it work correctly in IE, the style parameter

z-index:3

was added to the ./deps/nitrogen/src/elements/layout/element_lightbox.erl, so it will look as follows:

-module (element_lightbox).

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render_element(HtmlID, Record) ->
        Panel = #panel {
                class=lightbox,
                style="position: fixed; top: 0px; left: 0px; bottom: 0px; right: 0px; z-index:3; " 
                      ++ wf:to_list(Record#lightbox.style),


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Should the fix be applied to the very Nitrogen trunk? It seems reasonable.