Cygwin-based Windows Simulation and pkill

[hamishwillee]

There are various scripts we have that shut down the simulator, and which assume pkill is supported:

Tools/sitl_multiple_run.sh: line 18: pkill: command not found

Is there any way to either support pkill, or fake this?

[hamishwillee]

Specifically, this did not work in my first test: mavlink/MAVSDK#494 (comment) POSSIBLY because I had started the simulator twice, and I suspect the old version may not have been cleaned up properly.

[MaEtUgR]

pkill and the px4 shell shutdown command work with the correct cygwin packages. Here's the change for the script installation:
PX4/PX4-windows-toolchain@0719053

It will be in the next cygwin toolchain msi (0.4) which I'll generate when the jmavsim on master is fixed again #10098 .

[MaEtUgR]

Closing because it's now in version 0.4: PX4/PX4-Devguide#614