changed pytest syntax (split in two. doctest-modules and the rest) and remove init files in doc dir (nonsense)

Modified documentation and added doc test. Also changed some of the code according to the increase of test coverage

Modified documentation and added doc test. Also changed some of the code in the main WideDeep class to increase test coverage

Finished implementation of DeepDenseResnet. Adapated DeepDense code for consistency (simply renamed 'embed_p' to 'embed_dropout'). Adapted docs and README. Included unit test for DeepDenseResnet.

Wide embedding

Changed loss value printed on the screen for regression. From RMSE to MSE. Adjusted documentation. Also changed unit test for callbacks to the new Linear-Embedding implementation, which implied incresing delta for early stopping

#18 Implementation of the Linear model that is the wide component via an Embedding layer. This helps optimize speed and memory usage. Adapted all the submodules accordingly

Precision recall

Changed README, wide_deep.py, docs, and examples according to the new metrics. Only thing left is adjust the notebooks