message: update UnderlineNav examples/docs
diff: @@ -3,7 +3,7 @@ import React from 'react'
  import {LiveEditor} from '@compositor/kit'
  import {NavLink} from 'react-router-dom'
  import ExampleHeading from '../doc-components/ExampleHeading'
  -import {Block, Text, UnderlineNav, UnderlineNavLink} from '../../src'
  +import {Block, Link, Text, UnderlineNav, UnderlineNavLink} from '../../src'
  const underlineNavLinkExample = `<UnderlineNav>
  <UnderlineNavLink href="#foo" selected>
  @@ -13,18 +13,10 @@ const underlineNavLinkExample = `<UnderlineNav>
  <UnderlineNavLink href="#baz">Baz</UnderlineNavLink>
  </UnderlineNav>`
  -const linkTagExample = `<UnderlineNav>
  - <a href="#foo">Foo</a>
  - <a href="#bar" selected>
  - Selected
  - </a>
  - <a href="#baz">Baz</a>
  -</UnderlineNav>`
  -
  const navLinkExample = `<UnderlineNav>
  - <NavLink to="#foo">Foo</NavLink>
  - <NavLink to="#bar">Two</NavLink>
  - <NavLink to="/">Selected</NavLink>
  + <UnderlineNavLink tag={NavLink} to="#foo">Foo</UnderlineNavLink>
  + <UnderlineNavLink tag={NavLink} to="#bar">Two</UnderlineNavLink>
  + <UnderlineNavLink tag={NavLink} to="/">Selected</UnderlineNavLink>
  </UnderlineNav>`
  export default {
  @@ -38,18 +30,15 @@ export default {
  <LiveEditor code={underlineNavLinkExample} scope={{UnderlineNav, UnderlineNavLink}} />
  </Block>
  - <Block mb={4}>
  - <ExampleHeading>
  - Using <Text mono>{'<a>'}</Text> tags
  - </ExampleHeading>
  - <LiveEditor code={linkTagExample} scope={{UnderlineNav}} />
  - </Block>
  -
  <Block mb={4}>
  <ExampleHeading>
  Using <Text mono>{'<NavLink>'}</Text> from react-router
  </ExampleHeading>
  - <LiveEditor code={navLinkExample} scope={{UnderlineNav, NavLink}} />
  + <p>
  + To use UnderlineNav with <Link href="https://github.com/ReactTraining/react-router">react-router</Link> or <Link href="https://www.npmjs.com/package/react-router-dom">react-router-dom</Link>, pass <Text mono>{'tag={NavLink}'}</Text> and omit the <Text mono>selected</Text> prop.
  + This ensures that the NavLink gets <Text mono>activeClassName='selected'</Text>.
  + </p>
  + <LiveEditor code={navLinkExample} scope={{UnderlineNav, UnderlineNavLink, NavLink}} />
  </Block>
  </div>
  )
  