Add responsive storybook ui with persistent sidebars, controls on larger devices

[jvliwanag]

Is your feature request related to a problem? Please describe. While the current storybook UI fits well with mobile phones on portrait mode, devices with larger screens especially when on landscape mode can lend itself to having a persistent side bar, and even add-ons on some cases.

Describe the solution you'd like

Make the RN storybook UI responsive such that at a certain size, display the sidebar persistently, and possibly the addons at the bottom, similar to storybook web.

[dannyhw]

@jvliwanag this is already implemented in v8 beta

[dannyhw]

These are all the ondevice ui from react native storybook in v8

[jvliwanag]

Just migrated to v8 -- wow! Amazing!