The default is for hyphens to separate tokens in search terms: `gem-based` is equivalent to `gem based`.
This adds `search_tokenizer_separator` as a site configuation option, to support search for hyphenated words.
Because `page.title` (and `page.url`) is already escaped and page titles served by lunrjs do not need escaping, ampersands need to be unescaped to display properly in search results.
The code snippet on the search documentation is missing the `relUrl` parameter in each search result, and the `url` parameter is not an absolute URL.
This updates to match the formatted output of `search.rake`
