Don't expand calendar part of the index tree in the left pane when navigating on calendar-based pages

[Raphaël Hertzog]

As explained in http://bugs.debian.org/765745 when a user enabled the calendar widget and has calendar-based pages, he tends to use the calendar widget to browse through those pages. The fact that the calendar tree is expanded in the index pane every time that the current page changes to another calendar-based page makes it rather painful to use the index pane to navigate in other non-calendar based pages (because the list of pages in a given month is usually rather long, even more when you browse often through two consecutive months, the current one and the next one, for example when you're at the end of the current month).

So it would be nice to have an option to not expand the calendar tee in the index pane, or to not auto-select the current page when you navigate to a calendar-based page.

[Jaap Karssenberg (jaap.karssenberg)]

Patch available in rev 745, 746