Add cross-institution examples to awesome list

[saracarl]

I'd like to see a section highlight interoperability. Some content:

http://beyondwords2016.org/objects/leaves-from-an-antiphonal-and-a-gradual

http://content.fromthepage.com/iiif-at-tcdl-2017/

[jronallo]

Propose close after fromthepage is added to reading-viewing and beyondwords2016 is added to implementations.