Implement ability to read the json format in the importer.

src/ida_migrator/import_dialog.py

@@ -12,6 +12,14 @@ def __init__(self, file_path, *args, **kwargs):
 
     def populate_function_names(self):
         print('[IDA Migrator]: Loading functions...')
+        with open(self.file_path, "r") as f:
+            parsed_json = json.loads(f.read())
+            self.tblFunctions.setRowCount(parsed_json['functions_count'])
+            index = 0
+            for func in parsed_json['functions']:
+                self.append_table_item(index, func['address'], func['name'])
+                index += 1
+        print('[IDA Migrator]: Finished loading functions.')
 
     def on_start_clicked(self):
         print('started import')