added monotonic clock which is independend of clock jumps in the system clock

src/fsfw/osal/freertos/Clock.cpp

@@ -5,6 +5,7 @@
 
 #include "FreeRTOS.h"
 #include "fsfw/globalfunctions/timevalOperations.h"
+#include "fsfw/serviceinterface/ServiceInterfacePrinter.h"
 #include "fsfw/osal/freertos/Timekeeper.h"
 #include "task.h"
 
@@ -47,8 +48,9 @@ ReturnValue_t Clock::getClock(timeval* time) {
 }
 
 ReturnValue_t Clock::getClockMonotonic(timeval* time) {
-  // TODO: I don't actually know if the timekeeper is monotonic..
-  return getClock_timeval(time);
+	TickType_t ticks = Timekeeper::getTicks();
+	*time = Timekeeper::ticksToTimeval(ticks);
+  return returnvalue::OK;
 }
 
 ReturnValue_t Clock::getUptime(timeval* uptime) {