ALT_HOLD mode (take off and land)

**Details**:
take off and land in ALT_MODE
bad landing
No GPS connected
Bad barometer measurements
good IMUs
good stabilization (pitch and roll)

**Commads**:
*Stabilization*:
mavgraph.py 42.BIN "ATT.DesPitch" "ATT.Pitch" --flightmode=apm
mavgraph.py 42.BIN "ATT.DesRoll" "ATT.Roll" --flightmode=apm

*IMU*:
mavgraph.py 42.BIN "IMU.AccX" "IMU.AccY" "IMU.AccZ" --flightmode=apm

*Altitude measurements*:
mavgraph.py 42.BIN "CTUN.BarAlt" "CTUN.Alt" "CTUN.DAlt" --flightmode=apm

*GPS*
mavgraph.py 42.BIN "GPS.Lat" "GPS.Lng" --flightmode=apm