Allow to use custom cache provider

[legionus]

Add the ability to define a custom cache backends. Not only redis and inmemory.

[codecov]

Codecov Report

Merging #2580 into master will decrease coverage by 9.76%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master   #2580      +/-   ##
=========================================
- Coverage   60.87%   51.1%   -9.77%     
=========================================
  Files         129     130       +1     
  Lines       11876   11898      +22     
=========================================
- Hits         7229    6081    -1148     
- Misses       3744    5054    +1310     
+ Partials      903     763     -140

Impacted Files	Coverage Δ
registry/storage/cache/provider/cacheprovider.go	0% <0%> (ø)
registry/handlers/app.go	46.88% <0%> (-0.83%)	⬇️
registry/storage/driver/gcs/gcs.go	0.39% <0%> (-68.67%)	⬇️
registry/storage/driver/oss/oss.go	0.56% <0%> (-56.91%)	⬇️
registry/storage/driver/s3-goamz/s3.go	0.5% <0%> (-51.14%)	⬇️
registry/storage/driver/s3-aws/s3.go	4.15% <0%> (-50.98%)	⬇️
registry/client/transport/transport.go	69.69% <0%> (-9.1%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 83389a1...58c8dd7. Read the comment docs.

[milosgajdos]

@legionus mind rebasing?

[legionus]

@legionus mind rebasing?

@milosgajdos I made this PR 5 years ago. I stopped developing distribution a long time ago. If you do not see any benefit in this PR, then you can close it.

[milosgajdos]

Gotchya. I can take it over from here and rebase to a new PR. Let's keep it open for now if you dont mind. Thanks!

[legionus]

I don't mind :)

[milosgajdos]

Closing in favour of #4169