Added blur/opacity, image preview, and full view

Adding some extra features including:

Text shadow toggle - Make text shadow optional (goes hand-in-hand with below options)
Blur toggle - Set a blur amount on the image to increase legibility
Opacity toggle - Set a background color and bring down the opacity to increase legibility
Clean view - hides date-time, and temporarily disables blur/opacity
Full view - Resizes the image using object-fit: contain to give a full view of the image

Fraulk / second-look