`object_store` already hard codes `rustls` as the TLS implementation, so
we have been shipping a mix of `rustls` and `openssl`. For simplicity of
builds, we should consolidate to one, and that has to be `rustls`.
This changes `lancedb` from a "pure python" setuptools project to a
maturin project and adds a rust lancedb dependency.
The async python client is extremely minimal (only `connect` and
`Connection.table_names` are supported). The purpose of this PR is to
get the infrastructure in place for building out the rest of the async
client.
Although this is not technically a breaking change (no APIs are
changing) it is still a considerable change in the way the wheels are
built because they now include the native shared library.
