- Eliminate segment_urls and initialization_url
+ Introduce manifest_url (manifest may contain unfragmented data in this case url will be used for direct media URL and manifest_url for manifest itself correspondingly)
* Rewrite dashsegments downloader to use fragments data
* Improve generic mpd extraction
Update of the "FranceInter" radio extractor : webpages HTML structure
had changed, the extractor didn't work. So I updated this extractor to
get the mp3 URL and all details.