Tabs component

**Is your feature request related to a problem? Please describe.**
There are apps in the wild that are using Rimble which attempt to create a "tabs" functionality using buttons or text links or pills. I think it would be helpful to have a first-class Tabs component in Rimble.

**Describe the solution you'd like**
Tabs should have a UI that reflects an intuitive tab functionality. It should support stying for an active tab.

**Describe alternatives you've considered**
Re-create tabs using existing Rimble components and add to documentation for an easy copy-paste example for users.

**Additional context**
Check out heiswap demo for example of bootleg tabs:
- http://heiswap.exchange
- https://pedantic-kowalevski-1511ad.netlify.com/ (Ryan's implementation)