- v2.0 in PX4/Firmware (ca3e4a53): https://github.com/mavlink/c_library_v2/commit/2c4b0e9ff26ce4900a72335912e2604a1e9948de
    - v2.0 current upstream: https://github.com/mavlink/c_library_v2/commit/6404047979cadac62fecd75070cd995f1ca66ca2
    - Changes: https://github.com/mavlink/c_library_v2/compare/2c4b0e9ff26ce4900a72335912e2604a1e9948de...6404047979cadac62fecd75070cd995f1ca66ca2

6404047 2018-08-03 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/b4871443354d607298b6f67bedd6c473c69c659a
d0fb5b8 2018-08-03 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/1ba233efffb54a7ed634160cd11855b3f5021b74

- v2.0 in PX4/Firmware (5cac32de): https://github.com/mavlink/c_library_v2/commit/7014d02d665d5e8fa33f084f7c5f4dbcfd61b4b0
    - v2.0 current upstream: https://github.com/mavlink/c_library_v2/commit/2c4b0e9ff26ce4900a72335912e2604a1e9948de
    - Changes: https://github.com/mavlink/c_library_v2/compare/7014d02d665d5e8fa33f084f7c5f4dbcfd61b4b0...2c4b0e9ff26ce4900a72335912e2604a1e9948de

    2c4b0e9 2018-08-02 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/a31cd350d4c2046f2378fe64bb7b3da1cfa829f4
63f79b0 2018-08-02 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/8879d8e2f1ca51dbc0f4e57da0075076b1ade973
193557c 2018-08-01 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/e77128069d785b47dcc13033d555896ce28acf4c

This reverts commit 0928112a.

 - correct a gyro variable type, and add magnetometer values to ScaledIMU messages.

is executed at any time if triplet as valid yaw waypoint

Add MPC_YAW_MODE option for heading along trajectory, which will be the same as
option 0 (heading towards target) if trajectory is straight line

A line was too long, shrunk it

The Pixhack v3 comes with an external IST8310 in the GPS.

It's used further down again.

- use the orb topic safety to check the safety state, because the actual
  safety state can come from the IO
- fix initialization if circuit breaker is set