Add more options to the Export to DXF dialog

[DelazJ]

and update the screenshot to display al the columns Fixes #8957, fixes #9070

@gacarrillor I made a few tweaks to your PR in order to reference options labels in GUI

@mhugent I'd appreciate your review and suggestion for missing descriptions. I read many times the symbol blocks PR(s) description and discussion and read what blocks could be in dxf file but I'm unable to simply explain what happens with this option here and the relation with data-defined properties, to an end user. Thanks

[gacarrillor]

and update the screenshot to display al the columns Fixes #8957, fixes #9070

@gacarrillor I made a few tweaks to your PR in order to reference options labels in GUI

Looks good to me, thanks!