Reduce layout flicker on Region Details

[dlaliberte]

closes #637

Prerequisites:

• Unless it is a hotfix it should be merged against the dev branch
• Branch is up-to-date with the branch to be merged with, i.e. dev
• Build is successful
• Code is cleaned up and formatted

Summary

Change layout and formatting to keep legend columns stable as user hovers over various values.
Also fix legend color for first signal to match gray color in chart.

[netlify]

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[dlaliberte]

There are a couple edge cases that still need a bit of work. e.g. With one column, the table expands too much if the window is wide.

[tildechris]

Looks like there is still significant flicker:

I think we need to wait for the next release to take a closer look at this.

[tildechris]

Previous screengrab was from the main page, here's one from the region details view:

[dlaliberte]

Looks like there is still significant flicker:

Flickering tooltip is different from flickering layout of the charts and tables. The tooltip flickers less than it used to, but there are still some more cases when it is drawn off the window that it flickers.

I think we need to wait for the next release to take a closer look at this.

This change is about the flickering layout. It's pretty rock solid now. I wouldn't wait.

[tildechris]

Ah, as per our discussion, you fixed the flicker with the chart area, and the tooltip flicker is a different issue. Let's move forward with the review.

[tildechris]

LGTM. Thanks Daniel, you can merge.