Add landmarks to indicate major page areas

[carrythebanner]

Landmarks are used by assistive tech to identify major page elements. This helps people easily location common items like navigation, search, and the main page content.

• Put top matter which appears on every page in header; inside of that, use:
  • nav for navigation
  • role="search" on the search control's parent container, including the label etc. (not directly on the input element)
• Primary content in main
• Version info in footer

Additionally, all content should be within a landmark — if there's content outside of landmarks, then someone navigating by landmarks could miss it.