Update submodule sitl_gazebo to latest Thu Oct 29 20:40:02 EDT 2020
Update submodule sitl_gazebo to latest Thu Oct 29 20:40:02 EDT 2020

    - sitl_gazebo in PX4/Firmware (6b9dde59d6f66f5973dd2659f4a71a1e6307f70e): https://github.com/PX4/PX4-SITL_gazebo/commit/2451437c19ed9fcdf8a79990313e768c98aa15b6
    - sitl_gazebo current upstream: https://github.com/PX4/PX4-SITL_gazebo/commit/06e801fe8b5267e561f00d8847a6343cb2386ab6
    - Changes: https://github.com/PX4/PX4-SITL_gazebo/compare/2451437c19ed9fcdf8a79990313e768c98aa15b6...06e801fe8b5267e561f00d8847a6343cb2386ab6

    06e801f 2020-10-29 Nuno Marques - add missing generated models to git ignore (#644)
eafc98b 2020-10-28 JaeyoungLim - Move boat model to jinja templates (#641)

acfloria/Firmware,acfloria/Firmware,acfloria/Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,acfloria/Firmware,krbeverx/Firmware,krbeverx/Firmware,krbeverx/Firmware,acfloria/Firmware,acfloria/Firmware,krbeverx/Firmware,krbeverx/Firmware