Support graphene 3.0

Merge pull request graphql-python#33 from necaris/release-0.1

Bump to 0.1

Merge pull request graphql-python#27 from upsidetravel/try-pydantic-1.5

Update to support Pydantic 1.5

Merge pull request graphql-python#23 from upsidetravel/new-release

Bump version, update lockfile

Merge pull request graphql-python#14 from upsidetravel/fix/more-compa…

…tible

Make more compatible with recent Pydantic

Add support for forward / circular references

Try again with CircleCI

Initial release built from CI

...we hope!