Update to the last gl-rs api.
Add missing documentation on enums.
Update to the last nalgebra api.
Add a compiler bug notice on the readme.
Update to the last nalgebra api.
Update to the last rust.

Option `map` method does not give a reference to the wrapped element any more.
It is replaced by `as_ref().map`.
Remove the compiler bug notice.
window: add width/height setting constructor
window+camera: add variable passes, defaults to 1
add stereo side by side camera

make sure it works with shaders too, see examples/stereo.rs
oculus_stereo as a clone of wave without dt update

shader is loaded from a file so can be changed without recompiling.
Allow default keyboard handling on the stereo demo.
Remove an unnecessary clone.
Update the gl scissor when the viewport is resized.
Remove an useless variable from the oculus stereo post-processing effect.
Pass the homogeneous matrix by reference to the camera upload_mat method.
Add the authors file to give the list of contributors.
Update to the last rust.

Rc and RcMut are now on std.
Update to the last nalgebra api.
Update submodules.