Changes
- Merged System category
- Added device classes to system sensors
- Added management URL to system web interface
- Added firmware version to system category
- Added entity categories
- Added update device class for firmware update sensor
- Convert uptime to new HA style
- Added iot_class
- Fixed some devices having manufacturer name "detect"
- Fixed empty comments as tracker entity name (hash as first character)
- Added measurement state class to traffic sensor
- Updated device_state_attributes to use extra_state_attributes
- Changed DEVICE_CLASS_* attributes to device classes