Add support for the serial transport.

[jdiez17]

Describe the feature

Hi, I'd like to use the zenoh-link-serial transport from Python. It looks like zenoh-python uses the same default transports as in the zenoh Rust crate (based on this). Would it be possible to enable the transport_serial feature?

[wyfo]

Zenoh features can be enabled at installation using the command documented in #491:

pip install eclipse-zenoh --no-binary :all: --config-settings build-args="--features=zenoh/transport_serial"

[jdiez17]

Thanks!