Create or update the breadcrumbs in the site administration
pages where it is required.
Highlight the corresponding site adminstration tab.
Highlight the primary nav to Site administration when user
is navigating to any of the site administration pages.
Also changed the boostnavbar so that the nodes in the secondary
navigation are not shown in the breadcrumbs when user is in site
administration page.
This patch adds two new functions to the event base to allow deprecation of
the individual events, without entirely removing them from the UI.
This is different to our normal deprecation procedure because all events
must support display of historical data. It must also be possible to view
the event information in the event monitor.
