Allow to set the signal to stop a container in `docker run`:
- Use `--stop-signal` with docker-run to set the default signal the container will use to exit.
Signed-off-by: David Calavera <david.calavera@gmail.com>
SIGCHLD and SIGWINCH used in api/client (cli code) are not
available on Windows. Extracting into separate files with build
tags.
Signed-off-by: Ahmet Alp Balkan <ahmetb@microsoft.com>