Blender Git Loki

First working implementation of VideoDeckLink.

Doc: TBD
BL_Shader: allows to pass partially defined shader (e.g fragment without
vertex)

VideoDeckLink: wip, card opening done, GPUdirect tbd.

Add Windows DeckLink API, put Linux aside for now.

The VideoDeckLink object is still a stub but now it compiles and links
with DeckLink COM API and nVidia DVP library.
Only Windows & CMake working at the moment.
The nVidia DVP library is added in SVN win64_vc12 repo.

This branch adds support for Decklink capture card in the BGE.

Decklink capture cards from BlackMagicDesign are capable of capturing
high speed video stream such as FullHD on HDMI, also 3D. It will
be available in the VideoTexture module as a new type of texture source.
The capture data will be sent to the GPU using GPUDirect for best
performance.
It will be available for Linux and Windows.
This first commit is only a stub for Linux. Windows to be added.