sigmoid 0.3.0
==================

* add Rectified Linear Unit (ReLU)

* add leaky Rectified Linear Unit (leaky ReLU)

* redo documentation



sigmoid 0.2.0
==================

* add vignette

* add tanh derivative



sigmoid 0.1.0
===================

* initial release

* implement logistic and Gompertz

* implement inverses (logit and inverse Gompertz)

* implement SoftMax
