Polytope

- support `matplotlib >= 3.6.0`
- correct cases of infinite bounding box and empty polytope;
https://github.com/tulip-control/polytope/pull/89

- REL: require Python >= 3.8
- REL: require:
- `networkx >= 3.0`
- `numpy >= 1.24.1`
- `scipy >= 1.10.0`
- `setuptools >= 65.5.1`
- REL: extra require: `cvxopt == 1.3.0`
- TST: require `pytest >= 7.2.1`, instead of `nose`,
for Python >= 3.10 compatibility
- CI: test using GitHub Actions

API:
- add function `polytope.polytope.enumerate_integral_points()`
- always recompute the volume when calling the
function `polytope.polytope.volume()`
- add parameters `nsamples`, `seed` to
function `polytope.polytope.volume()`
- replace certain `assert` statements with
`raise` statements, raising `ValueError` or `AssertionError`

- require `cvxopt == 1.2.5` in `requirements/extras.txt`
to support Python 3.9

- customizable plotting in methods `Polytope.plot` and `Region.plot`

- rename method to `Polytope.contains`, was `are_inside`
- add method `contains` to `Region`
- deprecate function `polytope.is_inside`,
use `in` and `contains` instead
- add arg `solver` to function `lpsolve`
- refactor by introducing new module `solvers`
- support MOSEK as solver, via function `cvxopt.solvers.lp`
- require `numpy >= 1.10.0`
- require `matplotlib >= 2.0.0` for tests

- negate `numpy.array` with operator `~`