🍓 0.3.0

Adds support for async sessions. To use:

from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine
from strawberry_sqlalchemy_mapper import StrawberrySQLAlchemyLoader

url = "postgresql://..."
engine = create_async_engine(url)
sessionmaker = async_sessionmaker(engine)

loader = StrawberrySQLAlchemyLoader(async_bind_factory=sessionmaker)

Releases contributed by @mattalbr via #53