Add the possibility to send a signal to the processes by name or by ID.

##The goal

Add the possibility to send a signal to the workers selected by name or by id.

# The implementation
The PR adds a new command `sendSignal <signal> <id|name>`.
The implementation leverages on the methods that stop a process since those methods send a KILL signal to the process.

I replaced everywhere the method `stopProcessId` by `sendSignalToProcessId` and `stopProcessName` by `sendSignalToProcessName`.

please give feedback and discuss.