feat(config): allow overriding nested config objects
feat(config): allow overriding nested config objects

This makes it possible for the following URL params to work:

config.p2p.enabled=true&config.p2p.preferH264=true

jitsi/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,bgrozev/jitsi-meet,jitsi/jitsi-meet,bgrozev/jitsi-meet,bgrozev/jitsi-meet,bgrozev/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,bgrozev/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,gpolitis/jitsi-meet,gpolitis/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,jitsi/jitsi-meet,gpolitis/jitsi-meet,jitsi/jitsi-meet,bgrozev/jitsi-meet,gpolitis/jitsi-meet