Fetus ultrasound does not look initially render well - level is wrong

[aylward]

Initial rendering looks poor:

Shifting the opacity curve fixes it:

[floryst]

Related to supporting setting default presets for datasets.

[floryst]

The reason behind the bad rendering is because the sample dataset is taking the CT-AAA colormap rather than US-Fetal. We need to support setting default view config values from the sample dataset configuration.