List is now automatically fetched from nodes.tox.chat and placed in the
user config directory. The list is updated once every 30 days, and
will attempt to detect problems and re-fetch the list if necessary.
Also fixed a couple file descriptor leaks and cleaned some things up.
Parsing json manually like this is ugly, but this allows us to use the json formatted nodeslist file
at nodes.tox.chat instead of having to update the list by hand. We could also potentially
use curl to fetch the list and update it automatically.