unique border partition DataHandle

This MR extracts the UniqueBorderPartitionDataHandle from the ParallelISTL branch, since it might be useful also in other implementations.

src/amdis/utility/CMakeLists.txt

@@ -4,4 +4,5 @@ install(FILES
     LocalToGlobalAdapter.hpp
     MacroGridFactory.hpp
     QuadratureFactory.hpp
+    UniqueBorderPartition.hpp
 DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/amdis/utility)