Add annotation widget

[jmcglone]

As a user I should be able to annotate parts of a fully encoded EPUB at the sentence level using hypothes.is.

• [ ] if hypothes.is library is incorporated into head of a page that uses CSB, the annotation icon appears in the menu
• [ ] selecting/highlighting text on a page activates hypothes.is and allows a logged in hypothes.is user to annotate or highlight the text.
• [ ] clicking an annotation icon in the CSB menu activates the hypothes.is toolbar
• [ ] a canonical URL is set in the head to ensure annotations appear on all instances of the epub viewer
• [ ] should use open iconic pencil icon as annotation icon <span class="oi" data-glyph="pencil"></span>

question: hypothes.is would have to link the annotation to the Epub CFI? because the DOM is unpredictable?

[jmcglone]

@respinos It looks like EPUB.js has been updated to work with hypothesis. See this example on the hypothesis website:

https://web.hypothes.is/demos/epubjs/

more info: https://web.hypothes.is/blog/epub-annotation/

[respinos]

Investigate potential for conflict between search highlights and annotations.