fix ComputeOffAxisProjectionFrustum eyeseparation and near and far planes.
fix ComputeOffAxisProjectionFrustum eyeseparation and near and far planes.

I have modified the far plane to scale with the distance to the object as well as the depth of the object. I have also modified the near plane to scale with the distance to the object. These changes when combined provide much better stereo support across a wide variety of object scales.

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