enh(io): test if server is reachable before igtl tries to connect
Description
When igtl tries to connect to a distant server, timeout can be long to reach. As a matter of fact, this can imply very long blocking time without any notification of what happens.
Proposal
Add an option to Client::connect() function to first try to ping the server ip:port, with a customizable timeout (short default value). This can be used to quickly have an error if server is unreachable, and not use the blocking function connect from igtl if server isn't reachable at first place.
Outcomes
Error can be faster to get.