message: update Buttons example
diff: ### Buttons
  ```.jsx
  -<Box>
  +<FlexContainer flexDirection="column" alignItems="start" >
  <Button> Button </Button>
  -</Box>
  -<Box>
  <Button size="sm"> Button small </Button>
  -</Box>
  -<Box>
  <Button size="large"> Button large </Button>
  -</Box>
  -<Box>
  <ButtonDanger> ButtonDanger </ButtonDanger>
  -</Box>
  -<Box>
  <ButtonPrimary> ButtonPrimary </ButtonPrimary>
  -</Box>
  -<Box>
  <ButtonOutline> ButtonOutline </ButtonOutline>
  -</Box>
  -<Box>
  <Button block> Button block </Button>
  -</Box>
  -<Box>
  <Button linkStyle> Button linkStyle </Button>
  -</Box>
  -
  -<Box>
  <ButtonLink href="https://www.goatslive.com/">This is an {'<a>'} styled as a button</ButtonLink>
  -</Box>
  <ExampleHeading>Octicon Buttons</ExampleHeading>
  -<Box>
  +
  <OcticonButton icon={Pencil} label="Edit" onClick={() => alert('edit')} mr={3} />
  -</Box>
  -<Box>
  <Text color="red.5"><OcticonButton icon={X} label="Close" onClick={() => alert('close')} mr={3} /></Text>
  -</Box>
  -<Box>
  <OcticonButton icon={Hubot} size="large" label="ROBOT" onClick={() => alert('beep boop')} />
  -</Box>
  +</FlexContainer>
  ```
  export const meta = {displayName: 'Buttons'}
  