Auto-format code with black

[manics]

Closes https://github.com/ome/omero-py/issues/2

Opening for discussion.

• First commit configures pre-commit to run the black autoformatter
• Second commit is the result of pre-commit run --all-files

In future code can be formatted by running pre-commit run --all-files locally.

--exclude Since this will otherwise conflict with everything!

[sbesson]

Closing for now as this is conflicting and will need additional work/considerations if we want to introduce black