Renaming of variables and types and minor code changes

src/entrypoints/sdcard-benchmark.cpp

src/shared/drivers/Xbee/XbeeStatus.h

src/shared/drivers/servo/Servo.cpp

src/shared/drivers/servo/Servo.h

src/shared/drivers/timer/PWM.cpp

src/shared/drivers/timer/PWM.h

src/shared/math/Stats.cpp

src/shared/math/Stats.h

src/shared/scheduler/TaskScheduler.cpp

src/shared/scheduler/TaskScheduler.h

src/shared/scheduler/TaskSchedulerData.h

src/shared/sensors/SensorInfo.h

src/shared/sensors/SensorManager.cpp

src/shared/sensors/SensorManager.h

src/tests/catch/test-sensormanager-catch.cpp

src/tests/scheduler/test-taskscheduler.cpp

src/tests/sensors/calibration/test-calibration-stats.cpp