Add normalization levels

[FallingSnow]

Each level carries on to the next. This means level 3 includes all normalizations from level 1 to 3.

Level 0

• No normalization of any kind is applied

Level 1

• Videos are auto cropped

Level 2

• Subtitle Title normalization for subtitles streams already without a title
• Audio Title normalization for audio streams already without a title
• Language normalization detected from title if already exists. Search title for language and apply it to language tag in metadata.

Level 3

• Audio Normalization - “simple” audio RMS-based normalization to -2.0 dBFS
• Deinterlace videos.

Level 4

• Audio Normalization - loudnorm audio normalization

Level 5

This level may alter the video/audio/subtitles in undesirable ways, use caution.

• Audio Normalization - dynaudnorm audio normalization

[FallingSnow]

loudnorm is currently not supported by ffmpeg stable.

[FallingSnow]

These systems have been reworked with the 0.5.2 update and is no longer relevant.