[python] Add blend modes other than normal alpha blending

[Montspy]

Current compositing only support alpha blending an element (layer) on top of others.

W3 docs on compositing

Other popular blending modes:

• Multiply
• Screen
• Overlay
• Hue Blend
• Saturation blend
• Color blend
• Luminosity blend

Useful blending modes for masking:

• Source Over
• Destination Over
• Source In
• Destination In
• Source Out
• Destination Out
• Source Atop
• Destination Atop
• XOR

[Montspy]

This might be limited to static only NFT due to ffmpeg limited support for custom blend modes