Spotifywebapipython

* Updated `SpotifyClient` methods `PlayerActivateDevices` and `GetSpotifyConnectDevice` to re-create the ZeroconfConnect connection instance if the device IP address or port changed after Zeroconf rediscovery on a Disconnect call sequence.

* Modified `SpotifyDiscovery._OnServiceStateChange` method to process Zeroconf Update and Remove notifications.

* Modified `ZeroconfConnect.GetInformation` method logic to automatically retry the connection (after 250ms, 2s max) to the Spotify Connect Zeroconf device service if a "connection refused" was returned while trying to get device information. This was originally set to 10 seconds, which is far too long to wait for a device to become available.
* Updated `SpotifyClient` methods `PlayerActivateDevices` and `GetSpotifyConnectDevice` to rediscover the Spotify Connect Zeroconf device after a Disconnect call is issued. It has been found that some device manufacturers (e.g. Denon) stop and restart the Zeroconf server on the device after a `resetUsers` (e.g. disconnect) call is made, which changes the IP Port number that the device listens on for incoming connections.
* Removed the deprecated function `SpotifyConnect.PlayerResolveDeviceId` (since 2024/08/15); use the `GetSpotifyConnectDevice` method instead.

* Modified `ZeroconfConnect.GetInformation` method logic to automatically retry the connection (after 250ms, 10s max) to the Spotify Connect Zeroconf device service if a "connection refused" was returned while trying to get device information. The previous logic used a simple delay prior to the call and did not retry the connection, which resulted in the "connection refused" exceptions while trying to awaken devices. Some Spotify Connect devices take a little bit longer to start accepting connections again after a change.
* Added `lxml` package requirement to `setup.py`.

* Added `PlayerPlayState.IsEmpty` property; returns True if Spotify playstate returned an empty response; otherwise, false. This is a helper property, and is not part of the Spotify Web API specification.

* Added `SpotifyClient.GetCoverImageFile` that gets the contents of an image url and transfers the contents to the local file system. This method should only be used to download images for playlists that contain public domain images.
* Added `ImageObject.GetImageHighestResolutionWidth` that returns the highest resolution order image width from a list of `ImageObject` items.