Display available update on Info panel under version number

[SeanPM5]

Underneath where the version number is displayed on the Info panel, I think it would be helpful to tell the user whether they're up to date or not.

Then, when the user goes to report an issue, and the GitHub issue template directs them to this page, they'll see in a really user-friendly way that they're running an older/outdated version. And they'll hopefully upgrade before submitting their bug report. This is just one of several benefits.

Here is a mockup of the general idea, the styling could probably be improved upon:

(Text would only be red when there's an available update. Otherwise it would display something like "Home Assistant is up to date" in secondary text.)

Also, if the user is running Hass.io, this text could link them to /hassio/dashboard so they can update there.