Pos without an argument should return current position

[0x62]

Currently executing spotify pos returns an error:

$ spotify pos
Adjusting Spotify play position.
52:52: syntax error: Expected expression but found end of script. (-2741)

Instead, I suggest that it should return the current position:

$ spotify pos
Position: 3:01/4:55

Would a PR with this change be accepted?

[hnarayanan]

Yes, please!