Improve Addon

[villander]

@knownasilya what about, of we create a ROADMAP to insert into your addon all available options this repo ?
https://github.com/knownasilya/jquery-highlight

[knownasilya]

There are a few missing options. I don't think we need a ROADMAP file (they get outdated fast), but we could add a checklist here, and add a CHANGELOG.md (which is more useful).