message: Adjust default ambient occlusion strength
diff: <mix name="mix_ao" type="color3">
  <input name="bg" type="color3" value="1.0, 1.0, 1.0" />
  <input name="fg" type="color3" nodename="image_ao" />
  - <input name="mix" type="float" value="0.75" />
  + <input name="mix" type="float" value="0.85" />
  </mix>
  <output name="out" type="color3" nodename="mix_ao" />
  </nodegraph>
  