Improve the absolute time picker UX

[henrikno]

Describe the feature:
Improve the absolute time picker UX

Describe a specific use case for the feature:
Currently if I want to go back to a specific time frame I have to do a lot of "duplicate" clicks.
Say I want to go back to look at data from Sept 10, around noon.

Selecting the date is easy

But now it searches from there to "now", which is way too long time range, I'm looking for data around that time, say +2 hours.

So I have click the end time picker,

Click Absolute

Now it still defaults to "now" but in absolute terms.
So I have to go back to last month,

Then pick the same day

Then scroll up to find 2pm.

Then click Update.

If that wasn't the right time frame I have to do all the above again for both start and end time.

It would be great if when selecting an absolute start time, it would show a relative end time to that, say +1 hour, +6 hours, 24 etc.

[elasticmachine]

Pinging @elastic/kibana-visualizations (Team:Visualizations)

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)