Remove duplicate declaration
Remove duplicate declaration
build: Enable introspection

Still a ton of errors, and apparently g-ir-scanner has some issue with
the Graphene types.
Add some Graphene types annotations

The introspection scanner does not automatically associate a CamelCase
type to the C type, even if the corresponding introspection data clearly
matches the two. This means that we'll have to manually annotate all
Graphene types uses.

This is a simple commit that shows how.
build: Remove unnecessary scanner arguments
Merge pull request #4 from ebassi/introspection

Add support for introspection