Add the Angular Spectrum propagation method to simulate scintillation cases

[MatteoPasinetti]

• Add the Angular Spectrum propagation method through the atmosphere to allow the simulation of scintillation cases

• Add the propagation of non-constant amplitude to the PWFS, SHWFS, and BioEdge

• The scintillation map is carried by the source, just like the OPD and the phase

• Add an unwrapping method to use the diffractive phase and propagation modes to the atmosphere

• Add a tutorial demonstrating how to simulate a scintillation case and showing the tools around it

• Add metrics for scintillation (PSD, Rytov variance)

• Add a method to simulate specific Rytov variance cases