[CMake] Added option OGS_USE_PCH.

Applications/ApplicationsLib/CMakeLists.txt

Applications/CLI/CMakeLists.txt

Applications/DataExplorer/Base/CMakeLists.txt

Applications/DataExplorer/DataExplorer.cmake

Applications/DataExplorer/DataView/CMakeLists.txt

...ications/DataExplorer/DataView/DiagramView/CMakeLists.txt

Applications/DataExplorer/DataView/StratView/CMakeLists.txt

Applications/DataExplorer/VtkAct/CMakeLists.txt

Applications/DataExplorer/VtkVis/CMakeLists.txt

Applications/DataHolderLib/CMakeLists.txt

Applications/FileIO/CMakeLists.txt

Applications/InSituLib/CMakeLists.txt

Applications/Utils/OGSFileConverter/CMakeLists.txt

BaseLib/CMakeLists.txt

CMakeLists.txt

GeoLib/CMakeLists.txt

MaterialLib/CMakeLists.txt

MathLib/CMakeLists.txt

MeshGeoToolsLib/CMakeLists.txt

MeshLib/CMakeLists.txt