Suppress repeated file changes for collapsed changesets on timeline

[Mikael Relbe]

Repeated changes of a file causes it to be reported repeatedly within a collapsed changeset event on the timeline when trac.ini is configured like this:

[timeline]
changeset_collapse_events = true
changeset_show_files = -1

Example of timeline event report:

8:57 Changesets [1-4]
     (edit) test/text.txt
     (edit) test/text.txt
     (edit) test/text.txt
     (add)  test/text.txt

This ticket suggests that identical file changes within a collapsed changeset event are suppressed.

The example above would then become:

8:57 Changesets [1-4]
     (edit) test/text.txt
     (add)  test/text.txt

[Mikael Relbe]

patch to be applied on r11028