Allow for usage of different clocks in armarx::rtNow()

source/RobotAPI/components/units/RobotUnit/util/RtTiming.h

@@ -36,11 +36,11 @@ namespace armarx
     } // namespace rt_timing::constants
 
     inline IceUtil::Time
-    rtNow()
+    rtNow(clockid_t clockId = CLOCK_MONOTONIC_RAW)
     {
         using namespace rt_timing::constants;
         struct timespec ts;
-        clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
+        clock_gettime(clockId, &ts);
         return IceUtil::Time::microSeconds(ts.tv_sec * seconds2MicroSeconds +
                                            ts.tv_nsec / nanoSeconds2MicroSeconds);
     }