Sidebar: Site Picker Title + URL should link to view site

[alisterscott]

Originally raised by @melchoyce

I always click on the Site Picker Title + URL expecting it to bring me to the front-end of my site. I've seen other people do it in user tests, too. We should make it a link and ditch the View Site link in the sidebar.

Some feedback from @folletto

Note for historical context: we didn't do that before (i.e. September 2014) because we wanted to keep that area "free for future use", and so we didn't want to rush it before even having two sections in Calypso done. So we kept that on hold as much as possible.

I think we are now at a very different stage, and we have explored ins and outs enough.

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Whoever comes to design this piece, we need to address this bit in coordination with other pieces because they are currently all tied together even if it doesn't look like that. This ticket can't be solved just by making the area clickable because would bring in big inconsistencies.

This means that a design that works here needs to:

1. Make the site area clickable
2. Find a solution for the update badge currently showing there
3. Find a solution for the selected UI in the front-end
4. Coordinate possibly with the Editor