Update tickets to display image thumbnails if available:

1. Add image thumbnails to the bottom of each ticket reply if images are attached
   • Define the image extensions that may be used in thumbnails in the configuration file for the Support Manager
2. Include up to 6 images per row by default
   • Define this setting in the configuration file for the Support Manager
3. Display the image thumbnails for both admins and clients
4. When clicking the thumbnail, open a "lightbox"-type slider displaying the image at a larger width

Clients submit screenshots often into the ticket system, and in order to view the images they must be downloaded. Instead, we should detect common image file types, and display them inline as thumbnails (Bootstrap CSS), where the image can be clicked to display the full resolution version.

They could appear at the bottom of the ticket reply, perhaps 4 across, and generate a sort of gallery even.. clicking one opens it up in a modal with navigation arrows. The images could still remain at the top by filename for direct download along with other attachments, but this will make things easy.