reader button issues

[eshellman]

CORS has been set for ebook files in S3, (and it works!) but we need to show the reader button only when an ebook in our s3 is available.

We also need to figure out a behavior for the "Read It Now" button on the bookpanel. Seems to me it should be the reader when available.

[eshellman]

I like to put the logic for reader availability on the work object (in bibmodels)

[eshellman]

I think you can just use {% if work.epubfiles %}