revlogv2: allow upgrading to v2 Revlogv2 implies sidedata. Right now sidedata is not really used in production, and Revlogv2 will be used for the first production-ready version of sidedata support. Differential Revision: https://phab.mercurial-scm.org/D9844

[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true