Merge remote-tracking branch 'upstream/master'

.gitlab-ci.yml

build-helpers/loopy.spec

build-helpers/make-linux-build-docker-inner.sh

loopy/__init__.py

loopy/check.py

loopy/codegen/control.py

loopy/compiled.py

loopy/kernel/__init__.py

loopy/target/pyopencl/__init__.py

test/test_dg.py

test/test_linalg.py

test/test_loopy.py