This is a read map issue to cover implementation activity for the plan discussed in #1956. The plan is:

1. Move /v2/<name>/tags/list to /v2/<name>/tags/_list with a redirect for backward compatibility. (New Tags API #2169)
2. Add new route /v2/<name>/tags/<reference> for a DELETE operation. This route will support only tag references. (New Tags API #2169)
3. Add new route /v2/<name>/manifests/_list for GET operation to retrieve a list of digests in a given repo. I am not sure if this route is a best choice, may be adding /v2/<name>/digests/_list would be a better option. (API to retrieve lists of manifest descriptors #2199)