Fix for tornado-server with deactivated accesslog doesn't log to normal log anymore
Merge from master for unique user ids, get_metadata,
fix Goodreads integration
Update Translation (merge NL, update DE)
* Add buttons to show/hide results from Douban & Google
* Trigger search with "Enter" key
* Use Underscore.js template instead of build HTML strings in JavaScript
* Keep click event handler in JavaScript instead of using HTML's `onclick`
* Normalize Douban & Google results
* Update cover image & add cover URL to the form input