XF2 Addons Lazy Load [img] 2.8.0

A zero query method for per user-group lazy loading of the [img] and [attach] tags in threads

• Require StandardLib v1.22.0+
• Support XF2.2+ width/height attributes for IMG/ATTACH tags and use an SVG with those exact dimensions to prevent page-reflows due to height changes
  • XF2.3 correctly sets the height attribute, while XF2.2 does not

• Fix XF2.3 lightbox support