Move maximization when managing client

Maximization of oversized windows must happen BEFORE keepInArea() is called
because that will through resizeWithChecks() lead to an artificial constrainment
to the WorkArea which is the combination of all screens minus all struts
this fails if only one screen struts and as a result the window is no more
bigger than FullArea which is used as maximization enforcing condition.
(Maximization must also happen AFTER placement, because otherwise the window
will eventually be maximized to the wrong MaximizeArea - Screens(s) - (local) struts
depending on xinerama settings)





FIXED-IN:4.8