v.0.4

Python2 compatibility;
Using the rules: https://github.com/ali5h/rules_pip to install dependencies.
Improvements and adjustments.

To upgrade:

http_archive(
    name = "rules_databricks",
    sha256 = "2c7800a2f1ba4e8ad8b31f86f0dcc366f65011f09c963a5d68b8df4ab1c84bae",
    strip_prefix = "rules_databricks-0.4",
    urls = [
        "https://github.com/acqio/rules_databricks/archive/v0.4.tar.gz"
    ],
)