Merge branch 'feature/vectorized-facet-integrals' into 'master'

python/dune/perftool/loopy/symbolic.py

python/dune/perftool/loopy/transformations/collect_rotate.py

python/dune/perftool/pdelab/geometry.py

python/dune/perftool/sumfact/__init__.py

python/dune/perftool/sumfact/amatrix.py

python/dune/perftool/sumfact/basis.py

python/dune/perftool/sumfact/sumfact.py

python/dune/perftool/sumfact/vectorization.py

test/sumfact/poisson/poisson_dg.mini