Bugfix in FindGSL module

Core/Algorithms/inc/Simulation.h

Core/Algorithms/src/OMPISimulation.cpp

Core/Algorithms/src/Simulation.cpp

Core/CMakeLists.txt

Fit/CMakeLists.txt

Tests/UnitTests/TestFit/CMakeLists.txt

Tests/UnitTests/TestGUI/CMakeLists.txt

ThirdParty/RootMinimizers/CMakeLists.txt

cmake/modules/FindGSL.cmake

cmake/modules/SearchInstalledSoftware.cmake

dev-tools/openmpi/batest/batest.cpp

dev-tools/openmpi/supermuc.sh