PID watch does not work with containers

[muzammil786]

OpenSLP's PID (process ID) watching capability that removes the stale endpoints if the process which published the endpoint dies does not work if the process is inside the containers. If the process is running inside a container, the PID inside the container is different from the PID on the host due to the container running in its own PID namespace. SLPD requires the actual PID (the corresponding host PID) of the local PID inside the container for its PID watching capability to function properly.

This problem can be fixed if OpenSLP reports on PID namespace along with the PID. Then SLPD can look for the corresponding host PID given the two parameters and use the host PID for its watching capability.