Upgrade commons-configuration to 2.x

[jsfr]

We're on 1.x right now. There is a migration guide here:

https://commons.apache.org/proper/commons-configuration/userguide/upgradeto2_0.html

[jsfr]

This won't be possible as we use the 1.x branch because that's what Archaius needs. However Archaius is in maintenance mode so we probably want to kill Archaius from the library completely and then get rid of commons-configuration or upgrade it then.