Ability to list buckets / containers that the auth'd account has access to

[pjbull]

Right now you need to know your bucket or container ahead of time, but most services provide a way to list the buckets or containers you can access.

Could be a separate cloud only function, could be on CloudPath("s3://").iterdir()

[pjbull]

The syntax CloudPath("s3://").iterdir() now works to list the buckets for cloud providers with buckets/containers.