Ktrain

New:
- *ktrain* now uses tf.keras (`tensorflow>=1.14,<=2.0`) instead of stand-alone Keras.

Changed:
- N/A

Fixed:
- N/A

New:
- N/A

Changed:

Fixed:
- added encoding argument when reading in word vectors to bypass error on Windows systems (PR 31)
- Change preprocessing defaults and apply special preprocessing in `text.eda.get_topic_model`
when non-English is detected.

New:
- N/A

Changed:
- N/A

Fixed:
- `TextPredictor.explain` now correcty supports non-English languages.
- Parameter `activation` is no longer ignored in `_build_bert` function

New:
- support for learning from unlabeled or partially-labeled text data
- unsupervised topic modeling with LDA
- one-class text classification to score documents based on similarity to a set of positive examples
- document recommendation engine

Changed:
- N/A


Fixed:
- Removed dangling reference to external 'stellargraph' dependency from `_load_model`, so that we rely solely on
local version of stellargraph

New:
- N/A

Changed:
- N/A


Fixed:
- Removed dangling reference to external 'stellargraph' dependency so that we rely solely on
local version of stellargraph

New:
- N/A

Changed:
- N/A


Fixed:
- store a local version of `stellargraph` to prevent it from installing `tensorflow-cpu`
and overriding existing `tensorflow-gpu` installation