Release 2.0.0 (openai#1444)

Releases 2.0.0 of evals. This is a major version bump because:
* openai-python is bumped to >1.0.0, which reflects a major breaking
change to many uses of the repo
* We haven't released a version since April, so it seems fair to bump to
2.0.0 since there may be significant breaking changes to the code in the
last 8 months

The release is successfully pushed to PyPi:
https://pypi.org/project/evals/. Updating the repo to reflect the new
version.

In future work, I'll set up a github action to publish versions to PyPi
when the version string is bumped

pyproject.toml

@@ -1,7 +1,8 @@
 [project]
 name = "evals"
-version = "1.0.3.post1"
+version = "2.0.0.post1"
 requires-python = ">=3.9"
+readme = "README.md"
 dependencies = [
     "mypy",
     "openai>=1.0.0",
@@ -35,6 +36,9 @@ dependencies = [
     "statsmodels",
 ]
 
+[project.urls]
+repository = "https://github.com/openai/evals"
+
 [project.optional-dependencies]
 formatters = [
     "black",