Change of API: move setting the EGL context back to the APP.
First try to convert the Stencil app to a dual (directly to Screen / through intermediate Framebuffer) mode.Doesn't work yet ( API is inconvenient / plain wrong )
Simplify setting up DistortedScreen.
1. Correct some bugs in DistortedRenderState2. Thus make the Stencil App work3. New icon for it
Beginnings of Stencil App.