* inital "just barely works" Fuse.js support
* implement FuseJavascript; refactor index_for_lang
* support search config
* move fuse index building to it's own file
* update doc of Search.index_format
* update config docs
* update search documentation
* use &str where possible
* use libs::serde_json
remmeber to commit Cargo.lock
* move extension logic to IndexFormat
* move the entire filename logic inside IndexFormat
* move elasticlunr to it's own module
* only create elasticlunr.min.js if we're actually using elasticlunr
* move ELASTICLUNR_JS to elasticlunr.js
* hide the details of search's submodules
* optionally include path
* explain include_path better
* remove references to stork
* replace if with match
* support include_description
* specify "permalink"
* move body cleaning and truncation to a function
* update truncate_content_length docs to specify *code points*
