Merge branch 'NEON' into 'master_pre_stage'

.gitlab-ci.yml

Doxyfile.in

Makefile.am

ci_test_scripts/generate_gitlab_ci_tests.py

ci_test_scripts/run_ci_tests.sh

ci_test_scripts/run_distcheck_tests.sh

ci_test_scripts/run_project_tests.sh

configure.ac

elpa/elpa_constants.h.in

src/elpa2/compute_hh_trafo.F90

...pa2/kernels/complex_128bit_256bit_512bit_BLOCK_template.c

src/elpa2/kernels/complex_avx-avx2_1hv_double_precision.c

src/elpa2/kernels/complex_avx-avx2_1hv_single_precision.c

src/elpa2/kernels/complex_avx-avx2_1hv_template.c

src/elpa2/kernels/complex_avx-avx2_2hv_double_precision.c

src/elpa2/kernels/complex_avx-avx2_2hv_single_precision.c

src/elpa2/kernels/complex_avx-avx2_2hv_template.c

src/elpa2/kernels/complex_avx512_1hv_double_precision.c

src/elpa2/kernels/complex_avx512_1hv_single_precision.c

src/elpa2/kernels/complex_avx512_1hv_template.c