add file modification

apk_frauder/src/zip_reader.rs

@@ -297,6 +297,8 @@ impl<T: Read + Seek> ZipFileReader<T> {
     }
 
     pub fn get_classes_file_info(&self) -> Vec<&FileInfo> {
+        // TODO: check for holes: if classesN.dex does not exist,
+        // classesM.dex for M>N are ignored.
         self.files
             .iter()
             .filter(|&file| match_dexfile_name(&file.get_name()))