Smile Adam: add support for heater_electric type Plugs

Merge pull request #172 from plugwise/heater_electric

Include `heater_electric` plug-type,  in new constant `SPECIAL_PLUG_TYPES`

Smile Adam: more bugfixes, improvements

Changes:

• Bugfix: update set_schedule_state() to handle multi thermostat scenario's
• Improve tracking of the last used schedule, needed due to the changes in set_schedule_state()
• Improve invalid schedule handling
• Update & add related testcases
• Naming cleanup

Bugfix for https://github.com/home-assistant/core/issues/68621

Merge pull request #170 from plugwise/legacy_anna_heater_fix

Fix legacy_anna missing heater_id

Smile: add more outputs

Changes:

• [Feature request] Add regulation_mode and regulation_modes to gateway dict, add related set-function
• [Feature request] Add max_boiler_temperature to heater_central dict, add related set-function
• Improve typing hints

Smile: bugfix and improve

Changes:

• Fix for plugwise/plugwise-beta#250
• Rename heatpump outdoor_temperature sensor to outdoor_air_temperature sensor

Fix for https://github.com/plugwise/plugwise-beta/issues/250

v0.16.9a0

Update changelog

Smile: bugfixes, continued

Changes:

• Fix for home-assistant/core#68003
• Refix solution for #158

Smile: Bugfixes, more changes and improvements

Updates:

• Fix for #158: error setting up for systems with an Anna and and Elga (heatpump).
• Block connecting to the Anna when an Adam is present (fixes pw-beta #231).
• Combine helper-functions, possible after removing code related to the device_state sensor.
• Remove single_master_thermostat() function and the related self's, no longer needed.
• Use .get() where possible.
• Implement walrus constructs ( := ) where possible.
• Improve and simplify.

Smile: various changes/improvements

Changes:

• Provide cooling_state and heating_state as binary_sensors, show cooling_state only when cooling is present
• Clean up gw_data, e.g. remove single_master_thermostat key

Smile: small improvements

• Move schedule debug-message to the correct position
• Code quality fixes