New models

[vitskvara]

Implement some of these models (probably in this order)

• [x] AE
• [ ] AE ensemble (or maybe KitNet?)
• [x] DAGMM = Deep autoencoding gaussian mixture model for unsupervised anomaly detection. Suggested by editor, it is actually a generative model.
• [x] REPEN = Learning representations of ultrahigh-dimensional data for random distance-based outlier detection. Suggested by editor.
• [ ] OCGAN - this one is actually my favorite generative model that we have missed.
• [ ] Other?

[janfrancu]

Updated check boxes and reopened for future use