[FEATURE] OpenSeadragon bookmark

[kayakr]

Overview of feature request
For some content, it would be good to pre-zoom the tiled image to a specific region of the image, e.g. to pick out a person in group photograph. This can be done by integrating an OpenSeadragon plugin such as https://github.com/openseadragon/bookmark-url, where the x,y, & zoom coordinates are recorded in the URL, e.g. /demo.html#zoom=3.720052605446381&x=0.4876712785928251&y=0.780348764785003

What kind of user is the feature intended for?
Users, in terms of a better user experience for certain large images.

What inspired the request?
Migrating from a previous site where such functionality was provided by legacy Zoomify component.

What existing behavior do you want changed?
Nil.

Any brand new behavior do you want to add to Islandora?

• Integrate OpenSeadragon plugin bookmark-url, perhaps via submodule to drupal/openseadragon.
• New field for tiled images to capture URL parameters, e.g. oom=3.720052605446381&x=0.4876712785928251&y=0.780348764785003

Any related open or closed issues to this feature request?
Nil.

[kayakr]

fyi, we are potentially going to build such a feature, but want to put this out there in case others have a similar request, or already have it.