Integration of secml-malware inside CounterFit

[zangobot]

This pull request will add the possibility of using some functionalities of SecML Malware inside CounterFit. The users is then able to use the load secml command for loading the framework inside CounterFit, and then use some attacks (header perturbation attacks, PE format attacks, GAMMA attacks). It also enables the usage of malware classifiers, as MalConv and GBDT trained on EMBER (MalConv is provided inside the library, while the user would need the tree weights stored inside the library, inside a particular folder).

[ghost]

All CLA requirements met.

[moohax]

Thanks Zango - we'll take a look.

[zangobot]

Hello! Any updates on the status of the pull request?