Set verbosity in configuration

[ocaballeror]

I find it kind of annoying when I launch multiple agents and they all start printing INFO level log messages without me being able to do anything. (#329)

I suggest we add a configuration parameter / environmental variable to set the level of logging messages that we want to print.

[Peque]

Updated your issue description and created a new issue for the "annoying INFO log messages": #329

[Peque]

See also #316. I guess integrating somehow standard's logging or other logging module would ease all of this.