• Cleanup calculation of vessel.pitch_yaw_roll
• Fix calculation of vessel.heading_direction()
• Remove vessel.pitch_horizon_relative and vessel.roll_horizon_relative as say were misleading and did not create "valid" results
• Added check for stack overflow of scripts
• Create bindings for all enums:
  • Instead of vessel.autopilot.mode = "Prograde" one should now use vessel.autopilot.mode = AutopilotMode.Prograde
• Basic resource transfer API ksp::resource