Search is less than brilliant

[calpaterson]

• [x] Switch back to default AND
• [ ] Add highlights to the UI
• [ ] Display rank for easier debugging
• [ ] Rework query to make it faster
• [ ] Add a way to do logical NOT
• [ ] Add a way to do logical AND and OR
• [ ] Add a site:example.com feature
• [x] Support either quote symbol - "/'