[formatsort] Remove misuse of 'preference'

'preference' is to be used only when the format is better that ALL qualities of a lower preference irrespective of ANY sorting order the user requests. See deezer.py for correct use of this

In the older sorting method, `preference`, `quality` and `language_preference` were functionally almost equivalent. So these disparities doesn't really matter there

Also, despite what the documentation says, the default for `preference` was actually 0 and not -1. I have tried to correct this and also account for it when converting `preference` to `quality`

youtube_dlc/extractor/arte.py

@@ -150,7 +150,6 @@ class ArteTVIE(ArteTVBaseIE):
 
             format = {
                 'format_id': format_id,
-                'preference': -10 if f.get('videoFormat') == 'M3U8' else None,
                 'language_preference': lang_pref,
                 'format_note': '%s, %s' % (f.get('versionCode'), f.get('versionLibelle')),
                 'width': int_or_none(f.get('width')),