536: added new view for notifications on dashboard

Closes #536 (closed)

If there exist new notifications, "New Notifications" panel is shown on dashboard. We show max 5 notifications (ordered) to take reasonable amount of space on the display.

When "mark as read" is clicked, button is deactivated and text is changed:

After updating the page, we will not see read notifications in the list.

Each message is a link, which leads to notification (f.e href="/notifications/6"). If notification is actionable, then we will se action button ("view application" in this case). It redirects the page to application and changes status for read.

ViewAll button links to all notifications.