Multiple fails results in one replacement only

[Peter Papp]

When multiple track fail from the same source plugin, quickly one after the other, then only one replacement is received. This must be examined and corrected. Suspected cause is that Qt combines same signals to compress event loop. At least that's how I remember.

[Peter Papp (ppeter)]

Updated the playlist and replacement logic in radiosource. This is not the final solution to this bug, but a step towards it.

[Peter Papp (ppeter)]

This happens only with Radio Source. Nothing to do with Qt signal handling.

Fix committed. It brings the possibility of this happening down as low as possible. However, can not be completely outruled, as this is the nature of the beast with SHOUTcast: their documentation states that their station IDs can and will change. Therefore banned and "unable to start" stations aren't known until a station's url is retrieved. And the url is not included in the station list, but is a separate query to SHOUTcast servers. Wish it wasn't so. The changing IDs force me to use temporary database, which makes the plugin memory and network intense.