Re-add the NIC module with all its functionality (hopefully...).
This introduces a new concept: Instead of having separate queries for
critical and warning (which really are just another set of states), a
module can now return a list of states for each widget. All the state
information is then merged together into a single theme. So, for
instance, the NIC module can return a state saying "critical -
wlan-down", which applies the theme information for both "critical" and
"wlan-down".
see #23