The current way to generate QGis descriptors is to call `make generate_qgis_descriptor`, after all applications have been generated. It would be more convenient to declare the descriptor file during `otb_create_application` macro. This way, each descriptor will be generated right after building the application, requiring a single call to `make`. Of course, a boolean option in CMake can be added to enable/disable this automatic generation of descriptors. Another proposal is to move the descriptor folder to `PREFIX/lib/otb/descriptors`.