Delete tags with API v2 (fixes #106)

[xgin]

Use API v2 to delete tags.
In particular GET /manifest by tag to obtain the correct digest to delete and then DELETE /blob by the digest. The sequence is described here: https://docs.docker.com/registry/spec/api/#deleting-an-image

Note that the API does not remove the image from file system, you have to execute garbage-collector, e.g. with crontab

I did not find how to delete repository, because the API DELETE /repository does not work.

Issue for reference #106

[eidam]

any chance to get this merged? 😄

[pkcakeout]

Travis tells us that NPM does not want us to have nice things... :-( Good effort though @xgin 👍 !

We probably need to wait until somebody can help out and fix the NPM dependencies before this can be merged...

[xgin]

Travis is waiting for #162 to be merged.
Feel free to checkout my fork https://github.com/xgin/docker-registry-frontend and image https://store.docker.com/community/images/ekazakov/docker-registry-frontend

[thiagowfx]

#162 has just been merged. How can we force a travis rebuild through the github UI? Oh, actually, we'd need to rebase first.

[odoucet]

it is now ready to be merged :) Can it be done ? This is a very awaited feature !

[slavniyteo]

Why it isn't merged yet? Lot of people is waiting for this merge =)

[stijndehaes]

Still no progress?

[quangnhut123]

Is it still in process ?

[skygragon]

Guys, are we blocking on review for this?

[ghost]

Very important feature! PR looks good 👍

[healermagnus]

hoping to see this soon

[Nitrosito]

Why not merged yet? :(
This is a important feature in V2