fix missing clean-core dependency in CMakeLists.txt
clean-core is required by glow-extras (e.g. in SceneConfig.hh). However, the dependency is not modeled for cmake.
clean-core is required by glow-extras (e.g. in SceneConfig.hh). However, the dependency is not modeled for cmake.
assigned to @ptrettner
merged
mentioned in commit 5bac719a