Porting existing weavers

I'm looking for a way to port existing weavers, especially the famous [PropertyChanged.Fody](https://github.com/Fody/PropertyChanged), to Malimbe.

I've added an entry to the FodyWeavers.xml and naively dropped the netstandard2.0 .dll from the nuget package, renaming it to PropertyChanged.Fody.dll. That makes Malimbe recognize it but fails with an infinite reimporting loop:
`Expected the weaver 'PropertyChanged, Version=3.3.3.0, Culture=neutral, PublicKeyToken=ee3ee20bcf148ddd' to reference Mono.Cecil.dll. The weaver needs to add a NuGet reference to FodyCecil version 3.0.`

If I read that correctly we need the weavers to compile against [FodyCecil ](https://www.nuget.org/packages/FodyCecil) which in turn seems to be deprecated since 2018.

@bddckr Can you maybe tell me if I'm on the right track or even provide some guideline for this?