Add a cleaning module

[OdysseasXenos]

I added two cleaning functions in sso/cleaning.py

• The first requires a dxy column (from sqrt(dx **2 + dy **2) ) with the reduced magnitude.
• The second does the same as the iterative filtering from asteroid_spinprops and doesn't require anything new.

I made them in such a way that that they take the required columns (phase, ra, dec, magnitude etc.) as function arguments (in contrast to the asteroid_spinprops functions)

In order to run ATLAS, the latest version of asteroid_spinprops version is required (which is on PyPi) and the reparametrization version of fink_utils (which I believe has been merged already).