feat: add foreign key support

src/lib.rs

@@ -42,7 +42,7 @@ mod tests {
     fn test_db_builder() {
         let facade = DbBuilderFacade{};
 
-        match facade.build("./example.json".to_string(), "test.db".to_string()) {
+        match facade.build("./example.json".to_string(), ":memory:".to_string()) {
             Ok(_) => {assert!(true)},
             Err(message) => {assert!(false, "{}", message)}
         }