Notifications: The notification system has been overhauled

Notifications are now shown in-line and over the editor, you will be
able to perform actions on them (undo, activate, dont show again, etc).
They are intended to be more informative and less obnoxious.
rn=

(integrated from master branch change 2d4d0c1 by Nathan Rijksen <n.rijksen@gmail.com>)
Notifications: Convert instances of old API usage to new API

(integrated from master branch change 93f3432 by Nathan Rijksen <n.rijksen@gmail.com>)
Breadcrumbs: Compatibility with new notification system

(integrated from master branch change 4815032 by Nathan Rijksen <n.rijksen@gmail.com>)
UI: Prefs: Store "show advanced" state regardless of whether OK/Cancel is pressed

(integrated from master branch change 5e75479 by Nathan Rijksen <n.rijksen@gmail.com>)
Notifications: Fix pref loading

(integrated from master branch change 3a703c0 by Nathan Rijksen <n.rijksen@gmail.com>)
Notifications: Disable debugging

(integrated from master branch change 88c835d by Nathan Rijksen <n.rijksen@gmail.com>)
UI: Color hud elements according to editor color scheme

(integrated from master branch change 875f30e by Nathan Rijksen <n.rijksen@gmail.com>)
Quicklaunch: Allow quick file opening/creation when there are no open buffers

rn=

(integrated from master branch change 9793af9 by Nathan Rijksen <n.rijksen@gmail.com>)
Startpage: The startpage has been retired

It is succeeded by existing built-in functionality as well as the
"getting started" dialog and the new "Quick Launch" page (seen when all
buffers are closed)
rn=

(integrated from master branch change 1752d2d by Nathan Rijksen <n.rijksen@gmail.com>)