Merge pull request #18 from wrongu/app-restructure

tooltips and weather null fix
Merge pull request #19 from wrongu/app-restructure

helpers.system_dict speedup with filter for latest
HVAC enums created and initialized
hvac enum migrations done; still need scraper update
electric schema migrations (TODO: scraper update)
updated name ChannelEntry=>CircuitEntry; updated electric scraper
added test code to electric/scrapers
updated urls and views since ChannelNameMap is gone
hvac scraper/model cleanup: CHOICES gone and DEFLOST=>DEFROST
status 0/2 switched (0=OK)
Merge branch 'app-restructure' into lookup-tables
Merge pull request #20 from wrongu/app-restructure

Solar hot water
AVERAGING of temporary values into permanent reading
why did I ever delete log.py?
IN PROGRESS
NetworkSensor updated for status responses
python 2.6 dict comprehension in water scraper
live greenhouse data (special case of arduino system)
removed markers from plots
Merge branch 'arduino_greenhouse_temporary' into lookup-tables

Conflicts:
	server/timeseries/helpers.py
	server/timeseries/templates/timeseries/live.html