Add support and examples for displaying images.

[witnessmenow]

Various image sizes come back in the currently playing track endpoint. It would be cool to have ability to display them on screens

Need to also test what happens if you are playing a song that doesn't have an album

[witnessmenow]

Added data for the smallest image to the struct that is returned from the currently playing track function.

I was able to get this working using this library:

https://github.com/Bodmer/TJpg_Decoder

Here is the code I used for it, but it rough: https://gist.github.com/witnessmenow/063dcd4b4407aa51afb4f6a0a442b5af

https://twitter.com/witnessmenow/status/1283558532818898944

ref: 8c516d2

[witnessmenow]

Added an example for the Matrix, will add more examples later

https://github.com/witnessmenow/arduino-spotify-api/blob/master/examples/esp32/displayAlbumArt/albumArtMatrix/albumArtMatrix.ino