Right now KWin moves minimized windows to the end of the task switcher's
ordering. However this is a rather confusing and undocumented behavior
that explicitly overrides the user's chosen sort ordering, be it
"Recently used" or "Stacking order". This makes it a hidden magic behavior
of the type that is at risk of being more annoying than useful.

This commit removes the special handling and lets minimized windows live
in the appropriate order in the task switcher.