add usable_battery_level to charges

lib/teslamate/log/charge.ex

@@ -10,6 +10,7 @@ defmodule TeslaMate.Log.Charge do
     field :battery_heater_on, :boolean
     field :battery_heater_no_power, :boolean
     field :battery_level, :integer
+    field :usable_battery_level, :integer
     field :charge_energy_added, :float
     field :charger_actual_current, :integer
     field :charger_phases, :integer, default: 1
@@ -37,6 +38,7 @@ defmodule TeslaMate.Log.Charge do
       :battery_heater_on,
       :battery_heater,
       :battery_level,
+      :usable_battery_level,
       :charge_energy_added,
       :charger_actual_current,
       :charger_phases,

lib/teslamate/vehicles/vehicle.ex

@@ -824,6 +824,7 @@ defmodule TeslaMate.Vehicles.Vehicle do
       battery_heater: vehicle.climate_state.battery_heater,
       battery_heater_no_power: vehicle.climate_state.battery_heater_no_power,
       battery_level: vehicle.charge_state.battery_level,
+      usable_battery_level: vehicle.charge_state.usable_battery_level,
       charge_energy_added: vehicle.charge_state.charge_energy_added,
       charger_actual_current: vehicle.charge_state.charger_actual_current,
       charger_phases: vehicle.charge_state.charger_phases,

priv/repo/migrations/20200116190926_charges_add_usable_battery_level.exs

@@ -0,0 +1,9 @@
+defmodule TeslaMate.Repo.Migrations.ChargesAddUsableBatteryLevel do
+  use Ecto.Migration
+
+  def change do
+    alter table(:charges) do
+      add(:usable_battery_level, :integer)
+    end
+  end
+end