.json shading filters rendered after red/blue anaglyph mode

Put the summary of the bug you're having here

*What I expected to happen was that each virtual camera would apply the .json shader first and the red/blue tint to each image afterward.

*What actually happened was the shader was rendered on top of the red/blue tint, in some cases removing the effect of the anaglyph by desaturating both images.

Steps to Reproduce:
1. activate 3d anaglyph mode
2. activate super secret settings
some shaders will not work with the anaglyph mode.
suggest this could be fixed by re-arranging render sequence from

read cameras left and right ->render 3d anaglyph -> render shader

to

read cameras left and right -> render shader -> render 3d anaglyph