v0.2.0

Everything from the three 0.2.0 candidates, tried on a real charger, plus
what an independent audit of the last one found. Coming from 0.1.2, read
Changed first: three timings are now set in minutes.

Added

• Car plugged in and Car charging, two yes/no sensors.
• Forced charging state: what the three charging buttons set, now
  readable and settable in one place.
• Charging current preset: sets the current to one of the presets from
  the app, so the app's slider stays in step with Home Assistant.
• Energy limit per charge: stops the charge after a set amount of
  energy; 0 switches the limit off.
• Charging duration: minutes of the current charge, or of the last one
  while no car is charging.
• Electricity price and Car consumption, both disabled by default:
  the market price of a dynamic tariff, with the day's prices as an
  attribute, and the consumption the app uses to show range.
• Minimum charge pause, Minimum charging interval, Forced
  single-phase duration and Simulated unplugging duration, set in
  seconds; disabled by default.
• The charger is discovered on the network: Home Assistant offers it by
  itself and asks only for the password. When a known charger has lost its
  connection and announces a new address, its entry follows. An entry that
  is connected stays where it is, and an entry set up by name keeps the
  name.

Changed

• Breaking: Minimum charging time, Phase switch delay and
  Phase switch interval are shown and set in minutes instead of
  milliseconds (15 instead of 900000). Automations and scripts that set
  them need their values divided by 60000. Fractions work: 0.5 is 30
  seconds. The charger itself still receives milliseconds.
• Uptime (disabled by default) reads in hours instead of milliseconds
  once you enable it. If you had enabled it already, it keeps milliseconds
  until you pick hours in the entity's settings.
• Error messages now appear in your Home Assistant language (English and
  German so far): a failed setting, a refused password, a lost connection.
  They used to be fixed English text.

Fixed

• A charger the entry already knows must announce the expected serial
  number before it is sent anything derived from the password. A different
  charger at the address used to receive that answer first and be refused
  only afterwards.
• A diagnostics download hides the load-balancing group ID and the Wi-Fi
  error message. Both are free text a charger may fill with something that
  identifies you; they were left readable because the reference charger
  sent them empty.
• A different charger answering at the address while Home Assistant is
  running now raises a repair notice that points to Reconfigure. The
  integration already stopped connecting, rightly, but said nothing: the
  entities just stayed unavailable.
• A password the charger refuses while Home Assistant is running now asks
  for a new one. The integration stopped reconnecting, as it should, but
  never said why: the charger just stayed unavailable until a reload.
• Reconnecting and disconnecting no longer trip over each other. A
  reconnect under way when the integration was unloaded or disconnected
  could open a connection after the teardown had finished, and a reconnect
  during a slow disconnect could report success for the very connection
  being closed. An unloaded integration now refuses a late reconnect
  instead of coming back to life behind it.
• When setup refuses a charger (a different device at the address, or one
  already set up), that reason is what you see, even if closing the
  connection fails as well. The closing error used to take its place.
• Entities can no longer go missing when the integration connects. The
  charger sends its first status in several pieces, and a live update
  arriving between two of them used to count as "all properties known" --
  whatever came later got no entity until the integration was reloaded.
• The restart button no longer reports a failure on every press. The
  charger restarts without ever answering the command, and waiting for that
  answer ran into a timeout each time.