AxisError did exist, but e.g. ComplexWarning wasn't even properly
included.

API: Add numpy.testing.overrides to aid testing of custom array containers

API: (cython) remove `long_t` and `ulong_t`

* DOC: Slightly improve error when gufunc axes has wrong size

My hope was to tweak it into something useful that:

    a @= b

can raise when `b` should have two dimensions and has two axes specified
but actually only has one.
I didn't succeed, but I still think it a slight improvement to give the
ufunc name and the actual core dimensions.

* ENH: Use AxisError when gufunc axes appear wrong due to the number of entries

This allows catching the error relatively targeted for in-place matmul `a @= b`
which may use this path.

* MAINT: Restore most TypeErrors (a bit more compexl than nice, but...)

* DOC: add a release note

Co-authored-by: mattip <matti.picus@gmail.com>

* make isnan, isinf, isfinite, signbit, nextafter aliases

* fixes from review

Co-authored-by: Sebastian Berg <sebastianb@nvidia.com>

This enables building with NumPy on Linux and macOS. Windows support
should be complete to, but is untested as of now and may need a few
tweaks. This contains:
- A set of `meson.build` files and related code generation script
  tweaks, header templates, etc.
- One CI job on Linux
- Basic docs on using Meson to build NumPy (not yet integrated in the
  html docs, it's too early for that - this is for early adopters right
  now).

The build should be complete, with the major exception of SIMD support.
The full test suite passes. See gh-22546 for the tracking issue with
detailed notes on the plan for switching NumPy to Meson as its build
system.

Co-authored-by: Stefan van der Walt <stefanv@berkeley.edu>

DEP: Finalize MachAr and machar deprecations

This removes the attributes on finfo and the "public" module.  It also
deprecates `np.core.MachAr`.  We should be able to get away with just
deleting it, but there seems little reason to not just deprecate it for now.