* FIX: broken select badge as user title
* selected id wasn’t pass to underlying component
* <none> was rendered as an html tag <none></none>
* overriding a badge name wouldn’t work as it was using badge.name and not badge.display_name
* adds a spec to ensure this behavior is correct
* renames `select-box-kit` into `select-kit`
* introduces `single-select` and `multi-select` as base components
* introduces {{search-advanced-category-chooser}} as a better component for selecting category in advanced search
* improves events handling in select-kit
* recreates color selection inputs using {{multi-select}} and a custom {{selected-color}} component
* replaces category-selector by a component using select-kit and based on multi-select
* improves positioning of wrapper
* removes the need for offscreen, and instead use `select-kit-header` as a base focus point for all select-kit based components
* introduces a formal plugin api for select-kit based components
* introduces a formal pattern for loading and updating select-kit based components:
```
computeValue()
computeContent()
mutateValue()
```
Neil Lalonde
Joffrey JAFFEUX
Régis Hanol
Robin Ward
Arpit Jalan
Guo Xiang Tan