Add a “Digital Accessibility” link on the footer

[sehilyi]

A “Digital Accessibility” link on the footer:

https://accessibility.huit.harvard.edu/digital-accessibility-policy

Encouraged by the Harvard University Disability Resources team

[sehilyi]

Some additional thoughts:

• metadata
  • aria-hidden for several elements for quicker navigation
• structure
  • should add alt-text for figures
  • enhance the semantic structure with headers (e.g., publication title can be <h3/>)