Zoom in on images inline, not open externally

[SebastianPrehn]

As part of the wiki, it would be preferable to have the images zoom in and potentially blur the surrounding text when zoomed in, instead of redirecting to only the image, or opening it in an external tab.

In order to get the following working, we'll need to add custom CSS and Javascript to handle it.

[SebastianPrehn]

We need to look into whether Sphinx supports adding classes to our images, to make searching for the correct image reliable.

We need to have the clickhandler loop over all the elements selected by the modified css selector