utils/ipc-sshtunnel: Allow hooks to be passed on the command line
The ipc-tap and ipc-inject utility scripts allow hooks to be passed
on the command line that implement custom behavior upon receipt of
certain topics or tags. However, because ipc-sshtunnel does not take
hooks as command line arguments, this functionality cannot be used
with tunnels established using ipc-sshtunnel.
This commit modifies ipc-sshtunnel so that users may specify hooks
that will be passed on to ipc-tap and ipc-inject.