follow-up refinements to crop image selection UI

[jywarren]

After #214 we may want to circle back to further refine the "drag to crop" workflow and UI, including:

• adding an Edit crop button to redefine the crop area

• potentially switch over to one of these better-maintained image selection libraries:

• https://www.npmjs.com/package/image-crop-element

• https://www.npmjs.com/package/image-area-selector

• https://www.npmjs.com/package/jquery-select-areas

From the former, which is this -- https://github.com/odyniec/imgareaselect/

[jywarren]

GitMate.io thinks the contributor most likely able to help you is @ccpandhare.

Possibly related issues are #5 (image cropping module), #205 (add "drag to crop" UI feature to Crop module), #85 (Rework UI Handling), #116 (Image overlay module), and #29 (Incorporate test images into tests).

[aashna27]

I would like to work on this.