message: Update root-level documentation for recent glutin redesign
diff: /*!
  Easy-to-use, high-level, OpenGL3+ wrapper.
  -Glium is based on two core cross-platform crates:
  +Glium is based on glutin - a cross-platform crate for building an OpenGL window and handling
  +application events.
  -- The **winit** crate for cross-platform events and windowing.
  -- The **glutin** crate for cross-platform GL context.
  -
  -Glium provides a **Display**, offering an API around a combined **winit::Window** and
  - **glutin::Context**.
  +Glium provides a **Display** which extends the **glutin::GlWindow** with a high-level, safe API.
  # Initialization
  @@ -18,20 +15,16 @@ extern crate glium;
  fn main() {
  // 1. The **winit::EventsLoop** for handling events.
  - let mut events_loop = glium::glutin::winit::EventsLoop::new();
  -
  - // 2. A **winit::Window** registered with the event loop.
  - let window = glium::glutin::winit::WindowBuilder::new()
  + let mut events_loop = glium::glutin::EventsLoop::new();
  + // 2. Parameters for building the Window.
  + let window = glium::glutin::WindowBuilder::new()
  .with_dimensions(1024, 768)
  - .with_title("Hello world")
  - .build(&events_loop)
  - .unwrap();
  -
  - // 3. A **glutin::Context** associated with the window.
  - let context = glium::glutin::ContextBuilder::new().build(&window).unwrap();
  -
  - // 4. Construct a display from the window and the associated context.
  - let display = glium::Display::new(window, context).unwrap();
  + .with_title("Hello world");
  + // 3. Parameters for building the OpenGL context.
  + let context = glium::glutin::ContextBuilder::new();
  + // 4. Build the Display with the given window and OpenGL context parameters and register the
  + // window with the events_loop.
  + let display = glium::Display::new(window, context, &events_loop).unwrap();
  }
  ```
  