Merge branch 'backend-rework' into ast_extensions

.gitlab-ci.yml

docs/source/api/types.rst

docs/source/conf.py

src/pystencils/backend/kernelcreation/typification.py

src/pystencils/backend/platforms/generic_gpu.py

src/pystencils/field.py

src/pystencils/sympyextensions/pointers.py

src/pystencils/sympyextensions/typed_sympy.py

src/pystencils/types/__init__.py

src/pystencils/types/meta.py

src/pystencils/types/parsing.py

src/pystencils/types/quick.py

src/pystencils/types/types.py

tests/nbackend/kernelcreation/test_typification.py

tests/nbackend/types/test_types.py