0.5.1

Changes

• Add automatic dual mode autopilot and target altitude:
  • Climb while below target, maintain (faster ground speed) while above
• Add flight simulation model .ipynb
• Autopilot improvements:
  • Smoother flight directors
  • Fix ETA rounding
  • Add flight path vector
  • Reduce kick time 5s -> 3s
  • Altitude display
  • Reset speed estimate on landing