feat(module:progress): support steps

[wzhudev]

close #4635

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/NG-ZORRO/ng-zorro-antd/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Application (the showcase website) / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[zorro-bot]

This preview will be available after the TravisCI is passed.

[codecov]

Codecov Report

Merging #4637 into master will decrease coverage by 0.07%.
The diff coverage is 93.33%.

@@            Coverage Diff             @@
##           master    #4637      +/-   ##
==========================================
- Coverage   93.23%   93.16%   -0.08%     
==========================================
  Files         519      523       +4     
  Lines       12822    12856      +34     
  Branches     2013     2021       +8     
==========================================
+ Hits        11955    11977      +22     
- Misses        452      461       +9     
- Partials      415      418       +3

Impacted Files	Coverage Δ
components/progress/nz-progress.component.ts	95.12% <93.33%> (-0.3%)	⬇️
components/select/nz-option-container.component.ts	76.19% <0%> (-14.29%)	⬇️
components/table/nz-th.component.ts	98.16% <0%> (-1.84%)	⬇️
...ents/time-picker/nz-time-picker-panel.component.ts	92.88% <0%> (-1.19%)	⬇️
components/carousel/nz-carousel.component.ts	93.15% <0%> (-0.23%)	⬇️
components/code-editor/nz-code-editor.component.ts	17.89% <0%> (-0.2%)	⬇️
components/progress/nz-progress.module.ts	100% <0%> (ø)	⬆️
components/empty/nz-embed-empty.component.ts	95.83% <0%> (ø)	⬆️
components/table/nz-table.component.ts	93.16% <0%> (ø)	⬆️
components/ng-zorro-antd.module.ts	33.33% <0%> (ø)
... and 7 more

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