The stop button is deactivated while playback is paused. It shouldn't be.

[Nocifer]

Describe the bug
As per title.

Expected behavior
The pause button stops playback but retains the current playback position, while the stop button stops playback and resets the playback position to the beginning of the currently playing track.

This means that it should be possible to first pause the track and then also stop/reset it completely without having to first unpause playback.

Additional context
Some more observations about the playback UI and behavior:

1. Clicking a second time on the stop button should reset the current playlist to its beginning.
2. The stop button should probably reside next to the play/pause button, as in most media players.
3. The previous/next track buttons should be the outermost buttons, i.e. they should switch positions with the rewind/skip buttons respectively.