Use SIMD vectorization for physics thorns

Experiment with SIMD vectorization

Experiment with SIMD vectorization (add missing file)

Arith: Avoid constexpr problems in div and dual

Arith: Improve constructors

Arith: Add mixed rational-integer operators

Arith: Support CUDA for simd types

CarpetX: Removed unused lambda

Loop: New type GF3D2index

CarpetX: Make GF3D5layout its own type

CarpetX: loop: Support SIMD masked load/store operations

CarpetX: Replace omp critical by C++ mutex

LLVM 11 crashes on omp critical statements in lambdas.

CarpetX: Replace constructor by assignment

CarpetX: Omit "(void)" in empty argument list declarations

CarpetX: Circumvent constexpr problems in prolongation operators

CarpetX: Replace constructors by assignments

DGWaveToy: Reformat code

Hydro: Reformat code

HydroToyCarpetX: Move attributes after function arguments

HydroToyGPU: Move attributes after function arguments

WaveToyGPU: Move attributes after function arguments

Weyl: Move attributes after function arguments

Z4c: Move attributes after function arguments

ODESovlers: Add helper function make_array

ODESolvers: Allow computed why arguments to check_valid

ODESolvers: Implement a more efficient linear combination algorithm

Avoid temporaries, parallelize via OpenMP and CUDA.

TwoPunctures: Reformat code

WaveToyMoL: Reformat code

Weyl: Only check assert conditions in debug mode

Weyl: Use symmetry for calculating Ricci tensor

Weyl: Experiment with optimizing calculating Riemann tensor

Weyl: Optimize array indexing

Z4c: Optimize array indexing

Arith: Update code to make it work with GCC, LLVM, and nvcc

Arith: Modernize tensor operations (vectors, tensors, Riemann tensors, etc.)

CarpetX: Modernize CUDA annotations

Hydro: Modernize SIMD annotations

HydroToyCarpetX: Modernize CUDA annotations

HydroToyGPU: Modernize CUDA annotations

WaveToyGPU: Modernize CUDA annotations

Weyl: Use SIMD

Z4c: Modernize tensor operations

Weyl: Remove unused file

Z4c: Remove unused file

Arith: Add alignment functions

Arith: Correct and simplify simd class

Weyl: Correct derivatives and tetrad

Z4c: Correct derivatives

Arith: Introduce anyisnan

Weyl: Improve handling coordinate singularities

Weyl: Clean up unused code