Review obstacles and penal + test. Not complete

Examples/testPenal.py

HySoP/hysop/domain/obstacle/cylinder.py

HySoP/hysop/domain/obstacle/cylinder2d.py

HySoP/hysop/domain/obstacle/obstacle.py

HySoP/hysop/domain/obstacle/obstacle_2D.py

HySoP/hysop/domain/obstacle/obstacle_3D.py

HySoP/hysop/domain/obstacle/sphere.py

HySoP/hysop/fields/continuous.py

HySoP/hysop/fields/scalar.py

HySoP/hysop/operator/discrete/diffusion_fft.py

HySoP/hysop/operator/discrete/penalization.py

HySoP/hysop/operator/energy_enstrophy.py

HySoP/hysop/operator/penalization.py

HySoP/setup.py.in