Elkm1

- Speak word, speak phrase helpers added (no constants for words/phrases)

- Add handling for ST (temperature) messages
- Users were disabled and not working; enabled and fixed
- Retrieve temperatures on startup added

- Add serial io dependency

- Breaking change: no longer need to call
elk.loop.run_until_complete(elk.connect()); now call elk.connect()
- Retrieve counter values that have a description
- Fix for HASS Recorder errors about not being JSON serializable

- Add asyncio serial support
- Add test program to test serial support (bin/test-serial); requires data
file that can be grokked from debug output of bin/elk
- Add proper command line parsing for bin/elk including URL as param
- URL can also be read from environment variable ELKM1_URL
- Add reconnect logic with exponetial backoff
- Add pause writing to Elk when in remote programming mode
- Add const for format of setting
- Add const for RP mode
- Change thermostat const to match semantics of other const (e.g.: FAN_ON
changed to ON, MODE_AUTO to AUTO, etc). Makes for better formatting when
using pretty_const

- Start of cleanup of cmdr.py; using attrs lib
- Change return on pretty_const to string (was tuple)
- First cut of adding disconnect handling
- Reconnect to be handler by client; will get a callback on disconnect
- Fix alarm armup/state/etc to char from int