Splayout

* Automatically search for Ansys Lumerical Python API.
* Add use_gpu option for fdtd_region.

* Topology region can be defined with fdtd_engine=None.
* Add auto_update option for mode expansion.
* Add waveguide simulation example.
* Refine inverse design example for direct binary search.
* Add layout generation example for direct binary search.
* Update readme.md
* Update api reference for pixelated regions.
* New functions in FDTDSimulation.
* Add boolean operations example and docs.

* Enable backward direction calculations for monitors in the adjoint method.

* Fix the format for call_fom and call_grad for the user-defined fom.
* Add api reference for ScalableToOptRegion3D and AdjointForMultiTO.

* Fix bugs for the wrong reset operations for the adjoint method classes.

* New adjoint method class: AdjointForMultiTO for multi-region topology optimization.
* New optimization region class: ScalableToOptRegion3D for scalable topology optimization.