Fixed mp4 video playback

Some new videos are not "avi" files but "mp4" files

(cherry picked from commit ccea680d28cb120e4a3273a871340b61de477b88)
Fix #1 (the way the media URL is constructed)

When accessing programs via "Toutes les émissions", the prefix is not part
of the href tag (as before), but when going directly to "@rrêt sur images",
the prefix is part of the href.
We check if the href starts with "http" or not.

Thanks to mossroy!

(cherry picked from commit 70d7b1f28912a96a5ddc3cdc2df2e67c75a3f0e0)
Fix navigation items

Remove the check on href.
I don't understand how this coud work. A tag is not a dict...

(cherry picked from commit 6cc9c72321836982961e88d547b50df4568ad060)
version 2.2.3