Use full name for generic types

[DavidBoone]

Use the full name for generic types not in any of the _defaultNamespaces namespaces.

Instead of public NpgsqlRange<int> ActiveWeeks { get; set; } Generates public NpgsqlTypes.NpgsqlRange<int> ActiveWeeks { get; set; }

BTW, thanks for the recent v7 release, huge improvements!