Allow later versions of Pyomo and Python

Previously Switch 2.0.9 required Pyomo <= 6.7.2, which is incompatible
with numpy >= 2.0, which would automatically be installed as part of the
pandas dependency after June 2024. This release updates metadata to
allow later versions of Pyomo that will work with numpy > 2.0. Note that
it is still possible for users to create a non-working environment by
installing Pyomo < 6.8.0 with numpy >= 2.0, but we assume most installations
will either use old versions of Pyomo with old versions of Numpy
or new versions of Pyomo with new versions of Numpy.

Update updates209.txt

Improve detection and reporting of unusual solver failures

Update changelog and add commit logs to repository

update CHANGELOG.md

Prefer simple conda installation in INSTALL.md

Add pint to dependencies (needed for Pyomo when testing)

Specify long_description_content_type in setup.py

Merge pull request #107 from switch-model/2.0.2

Version 2.0.2