We used to show New Features in a tab on the dashboard,
but this could get pushed down the page especially on
our hosting. In 043117ca13
we made a separate What's New page, so this commit removes
the dashboard tab and changes the admin notification to
send the admin to /admin/whats-new instead of the dashboard
tab.
Martin Brennan
Krzysztof Kotlarek
Jarek Radosz
Daniel Waterworth