Enhancements of the next version v0.4

[Alireza Khorshidi]

The following enhancements need to be implemented in the next version of Amp:

1. Amp v0.3 does not make use of accompanying fmodules. Fortran part should also get modularized in the context of Amp.
2. Cartesian scheme should be added to Amp.
3. Amp cannot be directly initialized yet as what we had before, say,

calc = BPNeural(...)

and

calc = CartesianNeural(...)

4. Parameters are not ASE Calculator parameter type, rather parameters are just regular dictionaries (That's why it currently breaks BP_test.py).

P.S. In this version calculator is initialized as

calc = AMP(fingerprints=Behler, regression=NeuralNetwork, Gs=..., weights=..., ...)

It might be preferable to initialize it in turn as

calc = AMP(fingerprints=Behler(Gs=..., ...), regression=NeuralNetwork(weights=..., ...))

but I could not figure out how that is possible!

[Alireza Khorshidi]

Impelemented.