Creating intermediate representation for Mutations

[thesuhas]

Currently copied over instrumentation from here. Need to extend to component model.

[thesuhas]

To extend to component model, need to add a Component struct and add the following:

• [x] Core Module
• [x] Alias
• [x] Type
• [x] Import
• [x] Export
• [x] Instance (Maybe, not added to web assembly spec yet)

[thesuhas]

@ejrgilbert @ahuoguo I'm almost done with the encoder function. I'm currently facing issues on trying to encode the ComponentTypeSection. There seem to be a few recursive structs and I'm not sure what the best way is to deal with them.

ComponentType has a ComponentTypeDeclaration variant which in turn has a ComponentType variant and it becomes recursive.

Similarly, InstanceTypeDeclaration has a ComponentType variant which in turn has a InstanceTypeDeclaration variant. I'm trying to see the best way to write this without duplicating code too much, which I fear has already become an issue.

The code is here if you want to check it out but I feel like it may not be that readable