OCaml GLES 3.0 bindings

This project aims at providing a portable way to do OpenGL (precisely GLES) application using OCaml. It comes in three parts:

 * Low level bindings which allow to call directly GLES functions.
   This binding tries to be reasonably type-safe using polymorphic
   variants to encode Glenum type. The low level bindings also provide
   some sanity checks for the size of bigarrays which allow to capture
   quite a lot of errors with clear messages.
 * High level bindings: to provide some auxiliary functions like
   matrix inversion and ease the development. For instance, to use
   shaders, with the high level bindings, you use compile_shader with
   the sources code, get a value of type unit program. Then, you can
   set the variables of the shaders (uniform or attributes), either as
   constant or function and get a function to finally run the shaders.
 * A way to open a window, start the main loop and interact. Currently
   only EGL under X11 is supported but it would be nice to have
   support for other platforms (windows, OSX, android, ios, wayland,
   ...) with exactly the same interface.

Authors

 * [3]Alexandre Miquel (initial low level bindings for GLES 2)
 * [4]Christophe Raffalli (partial port to GLES 3.0, high-level
   bindings and examples)