add firstRessource timers

[utix]

Add information for the first ressource (mainly the .html file):

• dns
• ssl
• firstByte

[patrickhulce]

Thanks for the PR @utix!

However, this repo is focused on providing speed index and perceptual speed index metrics. I'm concerned that by expanding the scope to include other types of information we lose that focus and begin to overlap (potentially inconsistently) with consuming tools. Perhaps other general performance trace processing tools might help you here instead, maybe lighthouse?

[utix]

This metrics are key metrics to improve the speed index.
for example without ssl reuse you can loose times
When you miss you cache, the firstByte is degraded.
This metrics can quickly explain a degradation of your speedIndex