Adds concrete types distinction to JSON ABI.

With the changes proposed in this PR, functions,loggedTypes,
messagesTypes and configurables will only rely on hash based ids of
concrete types.

This change is required because types on the types arrays can be
abstract types, so the hash based ids could not include the generic
parameters of the concrete types used.

For instance a method with two args, `Option<u64>` and `Option<u32>`,
would generate two distinct hash based ids based on `sha256("enum std::option::Option<u64>")`
and `sha256("enum std::option::Option<u32>")`, but there was a single type for Option.

With the proposed changes we can now have multiple hash based ids for
generic types, while still having access to the same generated types as
the new `concreteTypes` map easily to the `typesMetadata` (old `types`).