Auto-resize images to reduce payload size

[BlueSlug]

Automatically resize and compress images to reduce payload size as much as possible and improve page load times.

The Floe Project site has made use of the Sharp plugin to achieve this. Using this plugin in the past has caused issues with using partial templates, so implementation may involve moving partial template content into a parent template in order to avoid race conditions.

See these commits from the Floe Project site for details on implementation:
fluid-project/floeproject.org@072ab2b
fluid-project/floeproject.org@34bebbc