VR-3505: Capture versioning information from S3

[convoliution]

Still needs to be able to accept user-specified version_ids.
Figuring out the API is complicated because verta.dataset.S3() accepts either

• a single string
• a list of strings

that can be either

• a bucket
• a specific key!

I could separate out the multiple argument types into S3.read_bucket(bucket) and S3.read_object(key) utils similar to Python, but that would break the existing API and also make it more verbose to use.

[conradoverta]

The concern of adopting something like Python style isn't breaking or verbosity, but the fact that they represent very different styles. Python is divided because you are talking about multiple sources of information that would be confusing if they overlapped. On the other hand, giving a path to a bucket, or to an item, or to a list of them falls naturally inside the same class of "set of locations to register". So having an API similar to the one we have makes things simpler from user POV. We can expand what a location means besides just a string though.

[convoliution]

Ahhh, I see. I'd been trying to figure out what the conceptual distinction was!

[conradoverta]

I'm assuming you already put some data there.

[convoliution]

There is data there! I almost forgot:
@ravishetye fyi, you had created this bucket to test versioning with. I'm now using this bucket for our automated Client tests. If this would pose any problem for you, I can create a separate bucket.

[ravishetye]

go for it. just a related datapoint when we version stuff and delete the object, the object is not actually deleted. We need to delete the version to keep the s3 cost in control.