remove reduced-resources setting

Reduced resources setting was used to disable minimize effect and to show wireframe when moving or resizing windows.

Minimize effect still can be disabled by using enable-animations setting from org.gnome.desktop.interface schema. And if you are really trying to reduce resource usage you probably already have animations disabled.

Wireframe mode has not been updated/fixed to work with CSD windows and/or to exclude shadow/resize area from SSD windows. Also quickly testing with and without compositor wireframe sometimes leaves parts of frame on screen.

Considering that there has not been any bug report about broken wireframe mode I think it is time to remove it instead of wasting time trying to fix something that nobody is using.