`Breadcrumbs` is intended to hold one or more `Breadcrumb` components.  This provides an easy way to structure
navigation as commonly seen at the top of web pages.

Example:
```jsx harmony
<Breadcrumbs>
  <Breadcrumbs.Breadcrumb>
    <Anchor to="https://www.myapp.com/home">Home</Anchor>
  </Breadcrumbs.Breadcrumb>
  <Breadcrumbs.Breadcrumb>
    <Anchor to="https://www.myapp.com/accounts">Accounts</Anchor>
  </Breadcrumbs.Breadcrumb>
  <Breadcrumbs.Breadcrumb>Products</Breadcrumbs.Breadcrumb> <!-- User is currently here -->
</Breadcrumbs>
```
