[Files] Show last modified date of the folders in the 'Files' section

[learner3]

To display the last modified date when any files are added/removed/updated to the respective folders..

    (Why: It help track if any new changes were made and when)

There already seems to be a column/ field for the same; this shouldn't be any big issue to fix.

Thank you for your suggestions and support in advance.

[RyanSobeck]

Is there a reason that the file dates don't change when a course is copied / imported from one semester to another? The lack of change in the dates can make a course look very dated just because the content hasn't changed.