Update plugins/SettingsDMCSampler.py

Just updating that limit to be more consistent with other apps.
Merge pull request #98 from halgfx/patch-2

Update plugins/SettingsDMCSampler.py
Update plugins/BRDFVRayMtl.py
Update ui/properties_object.py

Regarding this: https://github.com/bdancer/vb25/issues/93
Update plugins/Exporter.py
Update ui/properties_render.py
Update render.py
Update render_ops.py