Search Improvements

[ES-Alexander]

• Maybe allow typing in the bar, instead of opening a popup?
• Show extra details on the listings like the section (instead of just page), and possibly a count of how many times the search term was found
• Add keyboard shortcut(s) to access search
  • e.g. Adidoks allows typing / to start a search, which is also a convention on GitHub and some other places
• Possibly switch search provider to Algolia
  • Need to consider effect on offline users (e.g. for providing docs in a BlueOS extension, for remote use)