added 2 commands that show the top tracks and albums played by a user.
There are some formatting decisions that will need to be taken.
Also the client library for the API seems exhausted. Missing some key
things. Yet to use a constructor the initialize an instance of the
client when plugin is called rather than under each function.
Signed-off-by: Pratyush Desai <pratyush.desai@liberta.casa>
