This commit adds an install script that runs on 'npm install'. Its
purpose is to download, extract and verify a specific version of
the windows-kill.exe binary.

I decided not add the - windows only - executable directly to this
project to keep the dependencies clear. Furthermore I did not use
the node-window-kill package, because it comes with node-gyp which
requires python and vs2017 build tools on the target machine.

This commit replaces the taskkill invocation with windows-kill.exe.

We are now sending a SIGINT POSIX signal to the node process in a
Windows context.

Known issues: The windows-kill.exe has to be triggered in a detached
process context, which currently flashes a terminal window on each
reload. Furthermore the 'restart' event is triggered twice on the bus.

This commit silences all errors from the wmic.exe process. Which is save,
because the error case is handled by falling back to the child.pid.

It also optimizes the windows-kill invocation by minimizing (hiding)
the terminal window and keeping it open until the process has finished.

…1720)

This commit replaces the provisioning script, which downloaded
a specific windows-kill.exe binary, with the binary itself.
We are using the x64 version of the windows-kill.exe from:
https://github.com/ElyDotDev/windows-kill/releases/tag/1.1.4

We are now embedding the binary with the project directly to
decrease the complexity and avoid breaking the build by external
changes. Actually the maintainer of windows-kill changed his
GitHub username recently from "alirdn" to "ElyDotDev" which
broke the provisioning script!

This commit adds back the hard shutdown behaviour under Windows
as an opt-in: If the --signal option is "SIGKILL" nodemon will
terminate the process group by force without waiting for the
process to clean-up. This matches a SIGKILL on a UNIX system.