Added Tests/lfs-data as of ufz/ogs-data@a9f0365.

Tests/lfs-data/Elliptic/cube_1x1x1_GroundWaterFlow/cube.py

...lfs-data/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e0.prj

.../Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e0_neumann.prj

...a/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e0_newton.prj

...tic/cube_1x1x1_GroundWaterFlow/cube_1e0_quadratic_hex.prj

...lfs-data/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e1.prj

.../Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e1_neumann.prj

...a/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e1_newton.prj

...lfs-data/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e2.prj

.../Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e2_neumann.prj

...a/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e2_newton.prj

...lfs-data/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e3.prj

...ic/cube_1x1x1_GroundWaterFlow/cube_1e3_bottom_neumann.prj

...ic/cube_1x1x1_GroundWaterFlow/cube_1e3_bottom_neumann.vtu

..._1x1x1_GroundWaterFlow/cube_1e3_bottom_neumann_newton.prj

...e_1x1x1_GroundWaterFlow/cube_1e3_calculatesurfaceflux.prj

.../Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e3_neumann.prj

...GroundWaterFlow/cube_1e3_neumann_calculatesurfaceflux.prj

...a/Elliptic/cube_1x1x1_GroundWaterFlow/cube_1e3_newton.prj

...iptic/cube_1x1x1_GroundWaterFlow/cube_1e3_top_neumann.prj