Removed no-op window close callback.

The window close flag is already set before the window close callback is
called.
Set final window title right away.

There is no need for a separate call to glfwSetWindowTitle.
Removed setting window hint to default value.

GLFW 3 has sane defaults for all hints.  The default for the depth bits
hint is 24.
Disabled building of GLFW examples and tests.
Removed dependency work already performed by GLFW.

The GLFW CMake files already find and export the GLFW_LIBRARIES variable
that contains all dependencies needed by GLFW, GLEW and the samples.
Removed bundled GLEW makefile replaced by CMake.

CMake will overwrite the bundled GLEW makefile with its own each time it
generates files, leading to an unclean Git tree.