Training datasets will be created directly before training a coordinate.
  FixedEffectDataset is merged into FixedEffectCoordinate;
  RandomEffectDataset is merged into RandomEffectCoordinate;
Random effect vector projection will be disabled

2. Scores are changed to use Dataframe
3. Residuals will be computed by using a UDF on the training DataFrame. For random effects, the per-entity models will first need to be joined to the DataFrame by REID. A single UDF will do all scoring for fixed and random effects at once.

…own sampler