Suggestion: support GLFW 3.x

[bvanevery]

GLFW has fairly recently released the 3.x series. It uses a glfw3.h header file that CEGUI's custom FindGLFW.cmake does not detect. I'm not sure how 3.x differs functionally from earlier versions as I'm still learning about GLFW.

[Ident]

Isn't glfw only used in the demos? in that sense GLFW 3.X is regularly fully supported, you just dont have support for it in the samples, you are free to use it in your own program. To support both the old and new GLFW versions we would have to look at the changes and probably do some version checks etc., I will look at it in the future, as I use GLFW myself in some of my projects using CEGUI, however this will not be too soon.