Add EOL info component

[floreks]

What this PR does / why we need it:

Features

• clusters running versions <1.16.0 are highlighted in the UI with a warning
  • in their respective detail views
  • on a project's cluster list
  • in the project list, projects containing EOL clusters are highlighted similarly
• the warning is of a higher severity (e.g. in red) so that in the future we can use a lower severity visual warning to show clusters which are not yet EOL, but will soon be
• the specific version value <1.16.0 is relatively easy to change in the future

### Design
@cschieder I could use some ideas here. We are already showing a warning icon for container linux clusters. I don't have any good ideas on how to nicely show more warnings/errors. We also need to differentiate between versions where end-of-life date has already passed (error) and not yet passed (warning).

# Update 2

Which issue(s) this PR fixes:
Fixes #2497

Release note:

Kubermatic Dashboard now supports end-of-life configuration for Kubernetes versions. All versions up to defined version will be marked as deprecated or soon-to-be deprecated in the UI. It can be defined in the config.json file as follows:
...
"end_of_life": {
  "1.17.9": "2020-07-01",
  "1.18.0": "2020-09-15"
}

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: floreks

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• OWNERS [floreks]

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[codecov]

Codecov Report

Merging #2520 into master will increase coverage by 0.32%.
The diff coverage is 85.88%.

@@            Coverage Diff             @@
##           master    #2520      +/-   ##
==========================================
+ Coverage   52.44%   52.77%   +0.32%     
==========================================
  Files         226      229       +3     
  Lines        7936     8012      +76     
  Branches      927      938      +11     
==========================================
+ Hits         4162     4228      +66     
- Misses       3771     3781      +10     
  Partials        3        3              

Impacted Files	Coverage Δ
src/app/app-config.service.ts	29.72% <0.00%> (-1.70%)	⬇️
.../components/notification/notification.component.ts	69.56% <0.00%> (ø)
...app/cluster/cluster-list/cluster-list.component.ts	75.49% <66.66%> (+0.49%)	⬆️
src/app/shared/components/eol/component.ts	76.47% <76.47%> (ø)
src/app/shared/components/chip/component.ts	80.00% <80.00%> (ø)
src/app/shared/services/eol.service.ts	90.90% <90.90%> (ø)
...luster-version/change-cluster-version.component.ts	97.77% <100.00%> (+0.34%)	⬆️
...details/version-picker/version-picker.component.ts	81.53% <100.00%> (+4.17%)	⬆️
src/app/shared/shared.module.ts	100.00% <100.00%> (ø)
...rc/app/testing/services/app-config-mock.service.ts	88.88% <100.00%> (+1.38%)	⬆️
... and 3 more

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[floreks]

@kdomanski

in the project list, projects containing EOL clusters are highlighted similarly

What about a case where there are multiple clusters within the project and some of them are near EOL and some of them use already deprecated versions?

Should we show multiple warnings/errors? Show only error with generic information about status?

Also, I think that this would have to be handled by the API directly since we do not get information about the clusters on the project list view and we shouldn't get all the clusters for all projects as it would be a very expensive operation. We'd need to modify the existing project list endpoint probably.

[floreks]

@cschieder PTAL at new screenshots.

[maciaszczykm]

/lgtm
/hold

[kubermatic-bot]

LGTM label has been added.

Git tree hash: a18b3d8d25ef8f46c29d723d15fb71231a512658

[floreks]

/test pre-dashboard-test-e2e

[floreks]

/hold cancel

[maciaszczykm]

/lgtm

[kubermatic-bot]

LGTM label has been added.

Git tree hash: 405f8c2f7195504796db2dbb84f0f9377d92957c