Detext

Correct 'feature_names' as a required field https://github.com/linkedin/detext/pull/42
Update smart-arg to 0.1.1 https://github.com/linkedin/detext/pull/44
Added references https://github.com/linkedin/detext/pull/45 https://github.com/linkedin/detext/pull/46

Changes:
* Use external dependency smart-arg instead of the temporary arg_suite solution (38 )
* Fix bugs related to text processing (40 )

test automatic release

1. computing dense representation of sparse features
2. allowing interactions between sparse features and wide features

More specifically, the model architecture changes from

dense_score = dense_ftrs -> MLP
sparse_score = sparse_ftrs -> Linear
final_score = dense_score + sparse_score

to

sparse_emb_ftrs = sparse_ftrs -> Dense(sp_emb_size)
all_ftrs = (dense_ftrs, sparse_emb_ftrs) -> Concatenate
final_score= all_ftrs -> MLP

See https://github.com/linkedin/detext/pull/12 for changes

expose tfrecord dataset transformation function for LinkedIn usage (10 )