distribute Python client library as a Conda package

**Is your feature request related to a problem? Please describe.**
I am not able to find and install the Python client library (`pulsar-client`) using the [Conda](https://docs.conda.io) package manager. Conda is the preferred package manager for a significant community of Python users.

**Describe the solution you'd like**
I would like `pulsar-client` to be built as a package in the [Conda package format](https://docs.conda.io/projects/conda/en/latest/user-guide/concepts/packages.html) and distributed through [conda-forge](https://conda-forge.org/).

This solution requires all dependencies of `pulsar-client` to be available as Conda packages. Most of the dependencies are already available from conda-forge. However, the `apache-bookkeeper-client` dependency (and its transitive dependencies) may need to be built and released as Conda packages.

**Describe alternatives you've considered**
`pulsar-client` is already distributed in Wheel format through [PyPI](https://pypi.org/project/pulsar-client/). This works as expected for users of `pip` and other similar package managers. However, the Wheel format is not convenient for users of Conda.