Merge branch 'bugfix/remove_global_using_namespace_units' into 'master'

Move using namespace units to namespace mantle_api

See merge request eclipse/simopenpass/scenario_api!22

MantleAPI/include/MantleAPI/Common/spline.h

@@ -24,8 +24,6 @@
 
 #include <tuple>
 
-using namespace units;
-
 namespace units
 {
 UNIT_ADD(jerk,
@@ -58,6 +56,8 @@ UNIT_ADD_CATEGORY_TRAIT(jerk_acceleration)
 
 namespace mantle_api
 {
+using namespace units;
+
 template <typename T>
 struct SplineSegment
 {