Adds the ability to create one or more zoom regions that show magnified or
enhanced views of the desktop. The magnifier provides options for:
* magnification factor,
* four mouse tracking modes common to screen magnifiers,
* positioning the magnified view in one of four screen location, or full screen,
* crosshairs to accentuate the position of the mouse,
* user preferences persistence via GConf (schemas in
.../data/gnome-shell.schemas).
* a DBus API to allow other processes to drive the magnifier as a service.
https://bugzilla.gnome.org/show_bug.cgi?id=595507
7b7c34a399