[parse_blend_file] Support the translucent material

[wahn]

There is a translucent material described here:

https://www.pbrt.org/fileformat-v3#materials

As an example how to do this with Cycles here two screenshots:

In the image above only Diffuse BSDF is used, whereas below the Translucent BSDF is mixed in:

[wahn]

Resolved by commiti a8e5b99.