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* Update the bundled pybind11 to version 2.7.1
* Fix conda-forge build on macos

* Add support for generating observation matrices (374).
* Allow the user to set fixed weather simulation parameters (379).
* Optimizations in the ground telescope simulation code (386).
* Support gain template fitting in the map making (381).
* Fixes to scheduling observations of solar system objects (408).
* Add support for simulating detector cross talk (380).
* Add support for common mode filtering (429).

Testing new deployment to PyPI.

Fixes several typos.

This re-enables support for directly calling MKL DFFT routines. A CMake check is added for MKL and if it is found, then MKL is used for both BLAS/LAPACK and FFTs. The MKL threading layer (GNU or Intel) is set at runtime based on the compiler used during build.

- Restore support for directly using Intel MKL for FFTs (PR 371, 372).
- Fixed bug in wind velocity during atmosphere simulations.

This fixes a bug found in the 2.3.9 release. Serial unit tests now explicitly disable MPI, so hopefully we will catch these in the future.