Better manage notifications to display
LL::NG portal loads notifications to display on a strange way :
- it loads all notifications concerning the user or all user (regardless if they are done),
- then it generates html for all these notifications (which is quite a heavy job)
- then, for each notification, it checks if it must be displayed or not (because already done, or because condition does not match)
- and it loads all notifications into session data, regardless if they are displayed.
It would be much more thrifty
- to generate html only for notifications which are displayed
- not to store any notification into session data (it doesn't seem to be used anywhere)
Besides, it would save memory to share XSLT parser object between apache threads, instead of recreating each time a use is authenticated.