Add stage2 results for california_housing. Add weight density plots for stage 2 exps

results/boston/stage2/weight_density_no_normalization.png

results/boston/stage2/weight_density_normalize_D.png

.../boston/stage2/weight_density_normalize_D_and_weights.png

results/boston/stage2/weight_density_normalize_weights.png

results/california_housing/stage2/losses.png

...fornia_housing/stage2/weight_density_no_normalization.png

.../california_housing/stage2/weight_density_normalize_D.png

...housing/stage2/weight_density_normalize_D_and_weights.png

...ornia_housing/stage2/weight_density_normalize_weights.png

results/diabetes/stage2/weight_density_no_normalization.png

results/diabetes/stage2/weight_density_normalize_D.png

...iabetes/stage2/weight_density_normalize_D_and_weights.png

results/diabetes/stage2/weight_density_normalize_weights.png

results/diamonds/stage2/weight_density_no_normalization.png

results/diamonds/stage2/weight_density_normalize_D.png

...iamonds/stage2/weight_density_normalize_D_and_weights.png

results/diamonds/stage2/weight_density_normalize_weights.png

results/kin8nm/stage2/weight_density_no_normalization.png

results/kin8nm/stage2/weight_density_normalize_D.png

.../kin8nm/stage2/weight_density_normalize_D_and_weights.png