Dimensional Label Support

[Birdasaur]

Standardize assigning labels to feature vector dimensions so that Hyperspace view can automatically relabel axes as dimensions are updated. There is already support built in to the Hyperspace view to do this but its thus far only utilized by explicit file loading activities.

• Update FeatureCollection and LabelConfig messages to allow optional dimensionLabels array.
• Update FeatureVector event handler to handle optional dimensionLabels data
• Hyperspace is updated whenever Dimension Label message is received
• new UI component that lists all dimensional labels in order
• allow direct text editing of individual dimension labels.
• Add/Remove individual dimensional labels. (default string is just "Factor")
• Clear all dimensional labels button