Merge pull request #869 from wenqing/output_VTK_PETSc

FileIO/VtkIO/VtuInterface-impl.h

FileIO/VtkIO/VtuInterface.cpp

FileIO/VtkIO/VtuInterface.h

FileIO/readMeshFromFile.cpp

ProcessLib/GroundwaterFlowProcess.h

SimpleTests/MeshTests/MPI/CMakeLists.txt

Tests/CMakeLists.txt

Tests/Data/EllipticPETSc/cube_1e3.prj.md5

.../Data/EllipticPETSc/cube_1e3_pcs_0_ts_1_expected.pvtu.md5

...Data/EllipticPETSc/cube_1e3_pcs_0_ts_1_expected_0.vtu.md5

...Data/EllipticPETSc/cube_1e3_pcs_0_ts_1_expected_1.vtu.md5

...Data/EllipticPETSc/cube_1e3_pcs_0_ts_1_expected_2.vtu.md5

...llipticPETSc/cube_1e3_pcs_0_ts_1_expected_visual.pvtu.md5

Tests/Data/EllipticPETSc/cube_1x1x1.gml.md5

Tests/Data/EllipticPETSc/cube_1x1x1_hex_1e3.vtu.md5

...pticPETSc/cube_1x1x1_hex_1e3_partitioned_msh_cfg3.bin.md5

...pticPETSc/cube_1x1x1_hex_1e3_partitioned_msh_ele3.bin.md5

...icPETSc/cube_1x1x1_hex_1e3_partitioned_msh_ele_g3.bin.md5

...pticPETSc/cube_1x1x1_hex_1e3_partitioned_msh_nod3.bin.md5

Tests/Data/EllipticPETSc/quad_20x10_GroundWaterFlow.vtu.md5