Ability to add arguments for a config file

[kelunik]

Allow defining arguments that can be used in the config file, e.g.

• bin/aerys -c config.php -- --port 80 --host localhost or,
• bin/aerys -c config.php --args port:80 --args host:localhost

[bwoebi]

Pending issue upstream: thephpleague/climate#73

[kelunik]

I guess we can just recommend to use environment variables as well.

[kelunik]

I think this should be solved with a configuration for the app instead of process arguments.