Update runtime settings UI, add to PSI

[nathanmax]

Summary

Could you please state clearly what is the speed of the Network you Run your tests especially on the Google Insight Speed test page

[patrickhulce]

Thanks for filing @nathanmax! Definitely weird that we don't say anywhere in PSI the throttling settings like the regular Lighthouse report.

[paulirish]

Discussed and we had consensus to add the runtime setting block to the bottom of the PSI report. 👍

fwiw @nathanmax https://github.com/GoogleChrome/lighthouse/blob/master/docs/throttling.md has the details on the network throttling we use

[paulirish]

I have a doc exploring the new design: https://docs.google.com/document/d/1W66PKNDdcyNYDHnDBPvplyLAUfozdgk9FAZ3pjGieKA/edit#

The mock:

but in the doc i explore the text and extra details..