Add support for IGMP

[GyulyVGC]

Please consider adding support for IGMP protocol v1, v2, and v3.

[JulianSchmid]

I would consider it & I would add it to the library.

But I currently have not much time to implement this.

[GyulyVGC]

Take your time 👍

[jeff-moon]

I need this as well, will send a bunch of PRs your way for this!