This is used for example in application window titles, about dialogs, and default MITK packaging scripts. It raised quite some awareness in the past weeks as it is set to "experiments/sDMAS-2018.07" instead of "MITK v2018.04.2" (happens in CMake/mitkFunctionGetVersionDescription.cmake). While this should be fixed in principle it is certainly not the worst idea to at least allow to override it anyway. I want to introduce a CMake cache variable MITK_CUSTOM_REVISION_DESC for this purpose.