feat(demo): add universal support, add dockerfile

[IlyaSurmay]

• read and followed the CONTRIBUTING.md guide.
• built and tested the changes locally.
• added/updated API documentation.
  Closes Tabset component removeTab method doesn't work with Angular Universal #2778

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (development@d32cbbc). Click here to learn what that means.
The diff coverage is 30%.

@@              Coverage Diff               @@
##             development    #2925   +/-   ##
==============================================
  Coverage               ?   70.65%           
==============================================
  Files                  ?      137           
  Lines                  ?     4168           
  Branches               ?      740           
==============================================
  Hits                   ?     2945           
  Misses                 ?      914           
  Partials               ?      309

Impacted Files	Coverage Δ
src/tabs/tabset.component.ts	81.96% <0%> (ø)
src/popover/popover.directive.ts	78.57% <20%> (ø)
src/pagination/pager.component.ts	76.61% <50%> (ø)
src/pagination/pagination.component.ts	83.87% <50%> (ø)

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[YevheniiaMazur]

Warnings Unable to parse SourceMap appears and there are no dropdown with versions (both for demo.serve and demo.serve-universal run)

[valorkin]

@YevheniiaMazur we don't care about source maps