add directive for gauges
make update control reusable for later
implement very basic rename functions in client and server
drop InfoQuery and use libhexabus functionality instead
remove dead code
use endpoint registry to find endpoint units, submit last known value on create
remove SensorCollection and redefine sensors when the frontend balks
correctly display sensors at all times
clean sensor identification and data transmission

 * split sensor id into IP and EID externally
 * split name into name and unit