Marking new failed testcase special label and discuss abour new marks

[skhomuti]

I'm submitting a ...

• bug report
• feature request
• support request => Please do not submit support request here, see note at the top of this template.

What is the expected behavior?

I propose to discuss a new mark for new failed autotests, as well as a filter on these marks

Pull Request still in work, so here's a link to diff:
master...skhomuti:newfailed

Now implemented:

1. New failed tests are marked with a fa-warning icon. The test is new fallen if one previous result - passed. It may be worth considering five. Discussed
2. New filter for marks - new failed and flaky.

In my opinion also helpful:

1. Flaky for history, not retry
2. New passed testcases (failed for five times, now passed)
3. Always failed test cases (failed for ten or more times)

What is the motivation / use case for changing the behavior?

Very useful features for the analysis of a large number of autotests in projects in which there is no zero tolerance for fallen autotests

Please tell us about your environment:

Allure version	2.8.0
Test framework	Robot Framework@3.0.4
Allure adaptor	allure-robotframework@2.5.0

Other information