* chore: drop 3.6, add 3.11

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix: update to latest pybind11

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* chore: update for Python 3 only, drop Python 2

* style: run pre-commit

* ci: nicer update msgs if using pre-commit.ci

* chore: bump to version 2.7.1 & add nox

* ci: run simpler & more Windows runs

* ci: add wheels workflow

* fix: use classic build system for now

* fix: min CMake is still 3.15

* fix: support CMake 3.15+

See #1

* ci: add conda & wheel test, fix output location for conda