fix(tests): change run cypress tests for faster local run. Refactor test for making them readable

[YevheniiaMazur]

• edit e2e cypress tests for making them much readable and easier to use
• create tests examples and page objects for all demo pages
• move all e2e tests from separate file to one (due to cypress issue)
• change cypress config for run test using ng serve run instead of npm run demo.serve
• fix e2e tests due to demo changes
• add wait-on module for dynamic waiting for server boot, update cypress version to latest + update package-lock.json due to these changes
• update travis.yaml for dynamic waiting for server boot

[codecov]

Codecov Report

Merging #3742 into development will decrease coverage by 0.02%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #3742      +/-   ##
===============================================
- Coverage        72.23%   72.21%   -0.03%     
===============================================
  Files              252      252              
  Lines             8237     8237              
  Branches          1565     1565              
===============================================
- Hits              5950     5948       -2     
- Misses            1866     1867       +1     
- Partials           421      422       +1

Impacted Files	Coverage Δ
src/chronos/i18n/pl.ts	72.22% <0%> (-5.56%)	⬇️

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