Add token attributes to dummy dll

[knah]

Motivation: this would make it easier to work with il2cpp API at runtime, as tokens provide a nice and performant way to uniquely identify classes/methods without ambiguity of names and difficulties of overload resolution.
Mainly this would allow to generate better-performing assemblies using future versions of my assembly unhollower that could make use of token information

[Perfare]

I have an idea. It may not be necessary to set attribute, but just set the MetadataToken of Definition to be consistent with il2cpp.
typeDefinition.MetadataToken = new MetadataToken(typeDef.token);
By the way, even if the MetadataToken is not modified, the MetadataToken of the dummy dll after the output can always be consistent with that of il2cpp. It seems that the data of il2cpp is also stored in the order of tokens.

[knah]

I've checked generated tokens on current version, and they are unfortunately different from original ones. I'll look into your suggestion, if cecil allows that - it would be great. I'll comment on this PR with results

[knah]

I've tried that, and unfortunately setting MetadataToken values doesn't do anything - tokens are replaced with sequential values in ModuleWriter class in cecil when the assembly is written.

On the other hand, I can look a bit more into why tokens don't match - looks like nested types can cause misalignments

[Perfare]

Thanks for your feedback, maybe I should modify the logic of the nested types part to match it.

[Perfare]

I did some research, cecil uses depth-first traversal when writing modules, but breadth-first traversal can output values consistent with il2cpp.
So I think unless we modify the cecil code, we can only add token attributes to get the correct token.