The tour is not navigable with the keyboard

Expected:

• The focus is on the Next button
• (Shift) tab circles between the previous (when shown), the next, the close button
• The Escape key quits the tour (here, the Welcome to XWiki tour which is the first thing a user see)
• The Enter key does the same thing as the "Next" button

Bonus expectations:

• The Right key does the same thing as the "Next" button
• The Left key does the same thing as the "Previous" button

(actual: nothing of these things)