- use setOriginalsFromValues function right after elements had changed and
**only** with those elements
- add checkbox handling to setOriginalsFromValues to match hasChanged
- apply hasChanged after value is set to refresh originals after saving
- change parts that already set 'original' attribute manually

This was sort-of broken, because original attr never worked as intended. 
Also fix possible OOM for large WebUI images, since sending full config each time means that we need more memory to buffer and parse it.

1. Add thermostat to the espurna_modules in progmem.h
2. Add thermostat to webui, gulp, html, js.
3. in general.h MQTT_USE_JSON returned to 0 by default and 1 if thermostat enabled.

Bump npm version installed by travis
Update package-lock for latest npm version
Bump packages versions and clean-up unused
Missing datatables.js images to avoid warnings

tabs to spaces for consistency