Merge branch 'bug-11044-use-tarballs-for-external-projects' into bug-11046-clang-compatibility

• bug-11044-use-tarballs-for-external-projects: (57 commits) Use tarballs for external CTK and MITK-Data projects. COMP: APPEND_STRING is not available in CMake < 2.8.6. Add compiler flags to module and plug-in macros COMP: Added uServices vars to MITKConfig.cmake COMP: Fix non-atomic arithmetic COMP: Include missing header for Apple macros COMP: Tweak windows defines for including windows.h Pass doxygen CMake variables to external projects. Use new generalized CppMicroServices implementation. Improved documentation. Use the appropriate vtkInteractorStyleTrackballCamera for the 3D renderwindow. Fixed ordering of plug-ins. Removed irrelevant version_name_hash info and bumped PLUGIN_SYSTEM version to 2. Check if function mitkFunctionCheckMitkCompatibility is available. Added minimum required hash info. Support MITK compatibility checks based on rolling internal version numbers. Removed legacy CMake code. Added method documentation. Removed CoreUI directory and merged CoreUI/Bundles and Modules/Bundles. Updated PluginGenerator changelog and version number. ...