Hardware Skinning Support

- Supports GL, D3D9 & D3D11
- Extends vertex formats & shadergen to support blend indices and weights
- Adds basic support for using 4x3 matrices for shader constants
- Supports software fallback

Engine/source/shaderGen/shaderComp.cpp

@@ -32,6 +32,8 @@ ShaderConnector::ShaderConnector()
 {
    mCurTexElem = 0;
    mName[0] = '\0';
+   mCurBlendIndicesElem = 0;
+   mCurBlendWeightsElem = 0;
 }
 
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