Deal with external libraries

[CatarinaGamboa]

• Annotate libraries
• Use those annotations inside Latte
• we can use the @ExternalRefinementsFor("java.util.Iterator") annotation from liquidjava - you can check the examples in liquidjava at https://github.com/CatarinaGamboa/liquidjava/tree/main/liquidjava-example/src/main/java/testSuite/classes/arraylist_correct

[CatarinaGamboa]

Probably use a first pass to get the @External into the context and include their check in the visitors.