[downloader/f4m] If <pv-2.0> is in the manifest, add it to the fragments urls query (fixes #3176)

It's used in some akamai videos (for example for theplatform.com).
[theplatform] Extract all formats for f4m videos
[nbc] Update test
[theplatform] Correctly extract videos that don't use f4m or rtmp (reported in #3176)