Creates index data offline. Fixes #7
Prevent layout issues. Fixes #34
Version number works in gem and in built
Gem improvements

- Added config for directory for javascript: `js_dir`
- Added minified javascript to the gem and configured the generator to add it to the javascript directory if not present
- Split lunr out from the minified group so that the indexer can use it
Readme updates
Merge pull request #46 from jphastings/index

Offline search index generation