add time diff plugin

src/plugins/logfile/preprocesslineshook.py

@@ -0,0 +1,11 @@
+from abc import abstractmethod
+from typing import List, BinaryIO
+
+from src.ui.bigtext.line import Line
+
+
+class PreProcessLinesHook:
+
+    @abstractmethod
+    def pre_process_line(self, line: str, file_io: BinaryIO) -> str:
+        return line