Implement Options Menu

Implement an options menu drop-down that will allow users to customize the application with their own colors. Create a preferences file that stores this information so that the user does not have to customize their notepad every time.

Start by locating the Tkinter application's main entry point and any existing menu or configuration code. Determine how color preferences should be represented and persisted, then define the options menu and verify that customized colors remain after restarting the application.

Written by the indexing model from the issue text.