The new API no longer returns a list of numeric values alone. Instead,
it returns a tuple where the first element is the raw audio, and the
second element contains extra info on the rendered phonemes.
YAML isn't part of the Python standard library, while JSON is.
If we want `setup.py` to dynamically parse the available integration
manifest files in order to populate the extra dependencies, then it's
better to rely on a JSON format for manifest files - the parser is part
of the standard library and it doesn't require the user to install
`pyyaml` before `platypush`.
Fabio Manganiello