Multiple instances

Better memory management, enables to create and delete multiple instances of a network in a row. See the example "MLP_Circles_greedy"

Parallel processing

Add the possibility to do the forward and backward propagation on both processors of the ESP32, hopefully reaching x2 speedup.
I actually did not see any speedup at all. Maybe I did it wrong or the test cases are not suited for that (too small)?

Prediction

Changed the call to the predict method

Regularization

Implement weight regularization (see the 4 sectors example for details and results)

Softmax

Softmax implemented
Added an example

Faster version

Faster version
Mini batch management
To do: softmax activation for classification

Initial version

First version