sympy: Fix runtime integrated function shape

Change the shape of the array that the function to integrate returns
from (n,1) to a flat (n,) shape so that it is compatible with
`scipy.integrate.ode`.

There was a change in SciPy 1.17.0 that caused all the sympy tests to
fail. There were two changes to integration in that version, one or both
of which likely caused the issue.

0.9.2 release

First release candidate of 0.9.2

CI/CD: Fix `pymoca.__version__`

- Add a minimal setup.py to the project to allow versioneer to correctly
generate the _version.py file for deployment.

- Remove the setuptools dynamic versioning from pyproject.toml so we
will pick up the version from versioneer for both development and
deployment.

With these two changes, we now have the dirty flag during development to
invalidate the parse cache and the correct version number during
deployment for both the build artifacts and `pymoca.__version__`.

Without the setup.py change, `python -m build` would create correct
version numbers from a tag for the build artifacts, but `python -c
"import pymoca; print(pymoca.__version__)"` would give "0+unknown" from
the PyPI package. We previously had removed setup.py when migrating to
pyproject.toml.

Without the pyproject.toml change, the build was picking up the version
format from setuptools which did not have the dirty flag. The parse
cache logic currently depends on the dirty flag in the version string
generated from versioneer.

Test 1

CI/CD: Fix versioneer _version.py for deployment

Add a minimal setup.py to the project to allow versioneer to correctly
generate the _version.py file for deployment. Without it, `python -m
build` would create correct version numbers from a tag for the build
artifacts, but `python -c "import pymoca; print(pymoca.__version__)"`
would give "0+unknown" from the PyPI package. We previously had removed
the setup.py file when migrating to pyproject.toml.

Also remove the dynamic versioning from pyproject.toml so we will pick
up the version from versioneer during build when we are in development
mode. (The parse cache code currently depends on the dirty flag in the
version string generated from versioneer.) Previously the build was
picking up the version format from setuptools which did not have the
dirty flag.

With the above two changes, we now have the dirty flag during
development and the correct version number during deployment.

Make URLs in README acceptable to PyPI

The Python Package Index requires absolute URLs, so we need to use
GitHub URLs for all links in the README.

Make URLs in README acceptable to PyPI

The Python Package Index requires absolute URLs, so we need to use
GitHub URLs for all links in the README.

Include README image in `MANIFEST.in`

CI/CD: Include xml schema files in distribution

Include submodules in the deploy step so that the build process can
find the xml schema files specified in `MANIFEST.in`. Previous
distributions were apparently missing these files which I think means
the xml backend would not work in the distribution. I'm not going
to check because we don't actively develop the xml backend. However
I thought we would go ahead and fix this issue to remove the warning
from the build process.