API change for stick

• Improvement: Debounce relay state
• Improvement: Prioritize request so requests like switching a relay get send out before power measurement requests.
• Improvement: Dynamically change the refresh interval based on the actual discovered nodes with power measurement capabilities
• Added: New property attributes for USB-stick.
  The old methods are still available but will give a deprecate warning
  • Stick
    • devices (dict) - All discovered and supported plugwise devices with the MAC address as their key
    • joined_nodes (integer) - Total number of registered nodes at Plugwise Circle+
    • mac (string) - The MAC address of the USB-Stick
    • network_state (boolean) - The state (on-line/off-line) of the Plugwise network.
    • network_id (integer) - The ID of the Plugwise network.
    • port (string) - The port connection string
  • All plugwise devices
    • available (boolean) - The current network availability state of the device
    • battery_powered (boolean) - Indicates if device is battery powered
    • features (tuple) - List of supported attribute IDs
    • firmware_version (string) - Firmware version device is running
    • hardware_model (string) - Hardware model name
    • hardware_version (string) - Hardware version of device
    • last_update (datetime) - Date/time stamp of last received update from device
    • mac (string) - MAC address of device
    • measures_power (boolean) - Indicates if device supports power measurement
    • name (string) - Name of device based om hardware model and MAC address
    • ping (integer) - Network roundtrip time in milliseconds
    • rssi_in (integer) - Inbound RSSI level in DBm
    • rssi_out (integer) - Outbound RSSI level based on the received inbound RSSI level of the neighbor node in DBm
  • Scan devices
    • motion (boolean) - Current detection state of motion.
  • Sense devices
    • humidity (integer) - Last reported humidity value.
    • temperature (integer) - Last reported temperature value.
  • Circle/Circle+/Stealth devices
    • current_power_usage (float) - Current power usage (Watts) during the last second
    • current_power_usage_8_sec (float) - Current power usage (Watts) during the last 8 seconds
    • power_consumption_current_hour (float) - Total power consumption (kWh) this running hour
    • power_consumption_previous_hour (float) - Total power consumption (kWh) during the previous hour
    • power_consumption_today (float) - Total power consumption (kWh) of today
    • power_consumption_yesterday (float) - Total power consumption (kWh) during yesterday
    • power_production_current_hour (float) - Total power production (kWh) this hour
    • relay_state (boolean) - State of the output power relay. Setting this property will operate the relay
  • Switch devices
    • switch (boolean) - Last reported state of switch