Upgrade NumPy to 1.18.5, scipy to 1.4.1, add pybind11 package

[mkoeppe]

Follow-up from the update of numpy to 1.16.6 (#29429):

We update

• NumPy to the latest release, 1.18.5
• scipy to latest release, 1.4.1.
  (latest as of 2020-06-05; both versions (and also the upcoming numpy 1.19) support python >= 3.6)

Depends on #29480

CC: @isuruf @dimpase @jdemeyer @embray @slel @vbraun

Component: porting

Author: Matthias Koeppe

Branch/Commit: u/mkoeppe/trac/local_conda_forge_macos_standard__build_error_with_numpy @ 56a6fe1

Reviewer: Isuru Fernando, Dima Pasechnik

Issue created by migration from https://trac.sagemath.org/ticket/29425

[isuruf]

comment:1

Can you try setting NPY_DISTUTILS_APPEND_FLAGS=1 in the numpy build script?

[mkoeppe]

comment:2

This didn't make a difference

[mkoeppe]

comment:3

Upgrading numpy to 1.18.2 fixes it; but this will require a Cython upgrade too

[mkoeppe]

Branch: u/mkoeppe/local_conda_forge_macos_standard__build_error_with_numpy

[mkoeppe]

Commit: 6170b87

[mkoeppe]

Description changed:

--- 
+++ 
@@ -9,9 +9,17 @@
 ValueError: Could not lock sequences (None)
 ```
 
+This comes from the depth of NumPy's code that tries to determine ABI by inspecting some compiled code (https://github.com/numpy/numpy/blob/master/numpy/core/setup_common.py).
+
+An update of NumPy to latest release, 1.18.2 (which requires updating Cython to at least 0.29.14) fixes it.
+We update Cython to latest release, 0.29.16
+
+
 This can be tested with #29415:
 
 ```
   tox -e local-conda-forge-macos-standard
 ```
 
+
+

[mkoeppe]

Author: Matthias Koeppe

[mkoeppe]

New commits:

adf988d	build/pkgs/cython: Update to 0.29.16
6170b87	build/pkgs/numpy: Update numpy to 1.18.2, back out numpy-1.10.2-no-hardcode-blas.patch (does not apply)

[mkoeppe]

comment:7

Tests run at https://github.com/mkoeppe/sage/actions/runs/66127777

[isuruf]

comment:8

Cython URL can be set to https://pypi.io/packages/source/C/Cython/Cython-VERSION.tar.gz

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

078a653

build/pkgs/cython/checksums.ini: Use predictable URL for upstream_url pattern

[sagetrac-git]

Changed commit from 6170b87 to 078a653

[mkoeppe]

comment:10

Thanks!

[isuruf]

Reviewer: Isuru Fernando