Prominently display latest version number somewhere

[glenjamin]

As mentioned in yarnpkg/yarn#1730

It's currently non-trivial to figure out what the latest version of yarn is from the website, it'd be good to throw this number in the header somewhere.

It would also be good to provide some guidance during or near the installation instructions about how to upgrade yarn to the latest version - does self-update work regardless of the install method?

[Daniel15]

I've been meaning to add this while working on the nightly builds (show both the nightly version number and the stable version number).

does self-update work regardless of the install method?

Not yet, yarnpkg/yarn#1139 covers that.

[jamiebuilds]

@Daniel15 oh sorry, I added it to the navbar already

[Daniel15]

No worries @thejameskyle! 😄

I think we should mention it on the download page too.

[Haroenv]

Where should this be shown?

1. Before the copy

2. In the header

3. In the copy itself?

[vvo]

2. Seems better indeed