Add Accessibility Guide Link to Selector

[ymdahi]

Problem and Purpose

In addition to links to Tutorials and Examples, it would be ideal to have a link to an Accessibility Guide (AG) for each content type. The guide can reside on h5p.org or elsewhere. The purpose of the AG is to provide best practices for creating accessible learning module using each content type.

Proposed Solution

Background

LibreTexts, in coordination with Learnful and ASCCC OERI, have developed an Accessibility Guide for each content type. The AGs are publically available on LibreStudio, editable by the community, and can be retrieved via API:

https://studio.libretexts.org/api/h5p/accessibility?type=[Library Title]
e.g.: https://studio.libretexts.org/api/h5p/accessibility?type=Course%20Presentation

On LibreStudio, you can see the AGs are implemented as part of the front-end presentation when viewing a single h5p resource (look for the label "Accessibility").

Implementation

What is needed next is a button during the authoring process, e.g. in the H5P Editor. A proof-of-concept of this is currently live in LibreStudio. Refer to PR #163.

In this POC, I've simple added the 'Accessibility' button in h5peditor-library-selector.js as such:

this.$a11yUrl = ns.$(
    '<a class="h5p-a11y-url" target="_blank">' +
      '<span class="h5p-a11y-url-label">' + 
        'Accessibility' +
      '</span>' +
    '</a>'
  );

Other Considerations

The contents of the Accessibility Guides are:

1. Are preliminary and meant to be expanded upon.
2. Do not aim to provide an 'audit' of the content type's accessibility, rather steps/best-practices to improve accessibility when using the content type.
3. Would serve best if the community-at-large is able to suggest edits.
4. Should be hosted centrally, perhaps on h5p.org.