Merge branch 'develop' into 'master'

.gitlab-ci.yml

environment.yml

pyramid/analytic.py

pyramid/file_io/io_vectordata.py

pyramid/kernel.py

pyramid/plottools.py

requirements.txt

setup.cfg

setup.py

tests/test_analytic.py

tests/test_analytic/ref_phase_disc.npy

tests/test_analytic/ref_phase_slab.npy

tests/test_analytic/ref_phase_sphere.npy

tests/test_analytic/ref_phase_vort.npy

tests/test_costfunction.py

tests/test_costfunction/hess_ref.npy

tests/test_costfunction/jac_ref.npy

tests/test_costfunction/jac_vec_ref.npy

tests/test_costfunction/phasemap_ref.hdf5

tests/test_costfunction/zero_vec_cost.npy