Add Spectre Components

Add "Components" from Spectre, stories and tests for them:

* ~~Accordions~~
* Autocomplete
* ~~Avatars~~
* Badges
* Bars
* Breadcrumbs
* ~~Cards~~
* ~~Chips~~
* Empty states
* Menus
* ~~Modals~~
* ~~Navs~~
* Pagination
* Panels
* ~~Popovers~~
* Steps
* Tabs
* ~~Tiles~~
* Toasts
* Tooltips

1. Create an issue "Add component {ComponentName}" and state that you're working on it.

2. Follow the same code style as other components:
* Use Standard JS style
* Use component layout described in the readme and as seen in other component files

3. Make a pull request following the [PR template](https://github.com/CodeDraken/spectre-react/blob/master/PULL_REQUEST_TEMPLATE.md) and add a reference to the issue.

https://picturepan2.github.io/spectre/components.html

Start by reading the repository README and inspecting existing component files to understand the layout and Standard JS style. Choose one uncompleted Spectre component, create its separate issue as requested, then add the component, stories, and tests and use the PR template when submitting the pull request.

Vom Indexierungsmodell aus dem Issue-Text verfasst.