Add py.typed to yapapi to make the package PEP 561 compliant

[azawlocki]

Resolves #197

See #197 for details.

[etam]

Is it installed by poetry?

In python-poetry/poetry#1338 (comment) they say you need to add to pyproject.toml

[tool.poetry]
include = ["mypackage/py.typed"]

[azawlocki]

Is it installed by poetry?

In python-poetry/poetry#1338 (comment) they say you need to add to pyproject.toml

[tool.poetry]
include = ["mypackage/py.typed"]

@etam Yes, it is. Attaching a .tgz build by poetry.
yapapi-0.5.0a2.tar.gz

EDIT: I've also installed yapapi from a wheel package built by poetry in a fresh virtualenv and made sure that py.typed was there and that mypy was able to typecheck blender.py.

[etam]

indeed