[Direct3D11] Breaking changes of DeviceContext.Map in case MapFlags.DoNotWait is used. Now DeviceContext.Map with MapFlags.DoNotWait will return an empty DataBox is still in used by the GPU.
[Toolkit.Graphics] Add RenderTarget2D implicit cast to Direct3D11.Resource
[Toolkit.Graphics] Add support for Texture.GetData with DoNotWait new flag.
Update README.markdown
Adding proxy functionality in constant buffers (in effects framework) for sharing buffer from multiple effects
Adding Update method for constant buffers ( update a constant buffer without applying a pass )
Move to v4.5.1 framework (VS 2013)
build effects11 using 12.0 toolchain (vs2013)
[SharpDX] Add Equal(ref other) for vector/quaternion/matrix

Equal(ref other) is now also used in == and != operators
[SharpDX] Add Vector/Scalar component-wise addition and subtraction operators/functions
[SharpDX] Remove normalization from quaternion billboard functions and always normalize input in RotationLookAt
[SharpDX] Reuse stable Matrix3x3 functions to produce quaternions.

It gives better results and protects against negative Sqrt input and division with zero (NaN)