first open msg store, then open network in hxb_msg_bridge
add device interrogator to libhexabus

this class encapsulates simple communications, where one party sends a
packet and waits for a response, and resends said packet whenever it
detects a loss event. right now, a loss event is defined as "no respone
for one second".
[hexalog] track libklio changes

when we receive values for sensors we do not know yet, we cache the
values and ask the sensor for it's name. if we don't receive a name, the
readings are dropped.

we also now cache sensors to avoid reading the entire klio timezone
database every time a reading is received.