add support for custom file names

• nn can be saved under a custom file name
• a custom file can be specified to load a nn

add support for genetic algorithms

• add copy functionality
• add mutate functionality
• add functionality to merge two neural networks
• changed JSON-library from Json.simple to Google Gson

add WrongDimensionException

• add WrongDimensionException
• this exception will be thrown when the inputs of the user don't match with the dimension of the neural network

add support for different activation functions

Activation functions now available:

• Sigmoid
• Tanh
• ReLu

improved guessing method

guess method now returns an array instead of a 2d array

added multi-layer support

Features added:

• A NeuralNetwork can now have multiple hidden layers
• readFromFile returns now a new NeuralNetwork

added save and read to/from JSON-file

Features added:

• Saving a NeuralNetwork to a JSON-file
• Reading a NeuralNetwork from a JSON-file

initial release

v0.1-alpha

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