avformat_open_input fails when trying to play something while DB is being built

[Lukas Jirkovsky]

When the user tries to play a file while the database is being built, the needs_transcode_audio and needs_transcode_video functions returns -1 for all files. This is caused by ffmpeg failing to open the file with the "Protocol not found" error

[Lukas Jirkovsky]

Call the av_register_all(). Fixes issue#1 (bad protocol error when the DB is still being built).

→ <<cset 18a8be24b1ba>>