feat(module:carousel): support custom strategies

[wzhudev]

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?

Users can provide custom strategies to make transitions between carousel items.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[codecov]

Codecov Report

Merging #3501 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3501      +/-   ##
==========================================
+ Coverage    95.6%   95.61%   +<.01%     
==========================================
  Files         609      610       +1     
  Lines       13250    13258       +8     
  Branches     1810     1811       +1     
==========================================
+ Hits        12668    12676       +8     
  Misses        197      197              
  Partials      385      385

Impacted Files	Coverage Δ
components/carousel/nz-carousel.component.ts	93.71% <100%> (+0.24%)	⬆️
components/carousel/nz-carousel-definitions.ts	100% <100%> (ø)

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Deploy preview for ng-zorro-master ready!

Built with commit 855bcfe

https://deploy-preview-3501--ng-zorro-master.netlify.com