decrease value in usleep() from 50000 to 1000 (1ms), because driving the rover...

decrease value in usleep() from 50000 to 1000 (1ms), because driving the rover had to much delay, with 1 ms it works fine, tested successfully
refs 7953

org.fortiss.af3.platform.raspberry/trunk/lib/src/main.c

@@ -43,7 +43,7 @@ int main(int argc, char* argv[]) {
         // run endlessly
         while(1) {
             run_system();
-            usleep(50000);
+            usleep(1000);
         }
     }