Enable download (and zoom in) generated images

[chrisglein]

Notes

• That images are currently low res (256x256) and should be bumped back up (1024x1024) to make download interesting.
• Could add image size as a setting. I have it low to avoid usage costs during development. Perhaps tie that to debug mode?
• Related: Probably want ability to zoom in on the image even if the display size is initially small.
• Images are currently requested as a url. Would using the encoded option be better for this? Probably?
• Easy intermediate option: Enable Linking call to open the url that images come from