[v3] Deprecate stores that we don't expect to include in v3

[jhamman]

Following #1274, we expect the v3 release to include a smaller subset of stores. Specifically:

• MemoryStore
• DirectoryStore
• ZipFileStore
• FsspecStore

The thought is to move everything else to another library or, deprecate entirely.

As a first step, we should mark stores that we expect to move out of this library as deprecated and provide a discussion issue where we can direct users of those stores to.

TODOs here:

• [ ] deprecate existing stores
• [ ] open discussion issue
• [ ] make at least one Zarr-Python release ahead of the 3.0 release with this deprecation warning
• [ ] last step, remove existing stores

[d-v-b]

this is happening in #1791

[joshmoore]

Thanks for pushing this, guys. I find it unfortunate that the stores weren't in their own modules since I'd very much for keeping their git history. I'd be inclined even with the mega module to use a filter branch to populate the new repositories.

[jhamman]

Thanks for pushing this, guys. I find it unfortunate that the stores weren't in their own modules since I'd very much for keeping their git history. I'd be inclined even with the mega module to use a filter branch to populate the new repositories.

@joshmoore - its not too late to do this. I'd fully support someone taking this on.

[joshmoore]

it's not too late to do this.

definitely! :+1: