Updated to OpenTK 1.1.4

This release resolves a number of identified issues, adds experimental
support for Linux/KMS and synchronizes the OpenGL and OpenGL ES
bindings with the July 2014 Khronos specifications.

Changelog:

1. Fixed a memory leak in OpenGL functions accepting a string array.
2. Fixed an issue where `MakeCurrent()` might fail on Linux/X11 when
using the Nvidia closed-source drivers.
3. Fixed an issue where `GameWindow` might remain open on Linux/X11
after calling `Close()` or `Dispose()`.
4. Fixed a potential crash on Mac OS X systems without hardware
acceleration (e.g. virtual machines).
5. Fixed function parameters for the `OES_byte_coordinates` extension.
6. Fixed an issue where OpenTK would always perform a full rebuild even
when a partial rebuild could work.
7. Fixed all compilation warnings on VS2013 and Mono 3.4.0.
8. Improved OpenGL and OpenGL ES documentation on 'count' parameters.
9. New platform: Linux/KMS. You can now run OpenTK applications on a
Linux terminal without an X11 display server.
10. New OpenGL ES extensions:
  - ANDROID_extension_pack_es31a