Oculus VR DK2 Support

- Updated to work with 0.5.x SDK
- Uses Oculus Rendering rather than PostFX
- Stereo rendering refactored so more rendering info is grabbed from the DisplayDevice
- Implements an Offscreen Canvas for in-game gui with oculus
- Message dialogs and metrics display can now go to the OffScreen Canvas (if oculus demo is setup correctly)

Engine/source/gfx/gfxDevice.cpp

@@ -161,7 +161,6 @@ GFXDevice::GFXDevice()
    mAllowRender = true;
    mCurrentRenderStyle = RS_Standard;
    mCurrentProjectionOffset = Point2F::Zero;
-   mStereoEyeOffset = Point3F::Zero;
    mCanCurrentlyRender = false;
    mInitialized = false;
    
@@ -197,6 +196,9 @@ GFXDevice::GFXDevice()
    #elif defined TORQUE_OS_PS3
       GFXShader::addGlobalMacro( "TORQUE_OS_PS3" );            
    #endif
+
+   mStereoTargets[0] = NULL;
+   mStereoTargets[1] = NULL;
 }
 
 GFXDrawUtil* GFXDevice::getDrawUtil()