Untrack config.js AND config.json

The actual config filename shouldn't be tracked, as it prevents keeping
the project up to date with regular git pulls (uncommitted changes in
working tree).
Merge pull request #224 from dgw/untrack-config.js

Untrack config.js AND config.json
Fixing a bug where an empty networkRestriction config array wont accept any new connections. Also fixed a UF8 encoding issue with multibyte channel names. Closes #217