Custom convertes of data types that are not in the project scope

[manuelarte]

Imagine I have the following struct

type MyStruct {
  ID mssql.UniqueIdentifier `csv:"id"`
}

GoCSV can't unmarshall the id field because it does not know how to create the mssql.UniqueIdentifier, but I can't create my own converter because that struct is out of my scope, it would be nice to be able to add customs converters in other way.