Issues installing with python v3.12

[rjsmethurst]

numpy.distutils has been depreciated with Python v3.12 and the setup.py now doesn't run. Changing the first line of code in setup.py from:

from numpy.distutils.core import Extension, setup

to:

from setuptools import Extension, setup

(as recommended by setuptools documentation) let's the code run, but then the Extension module runs into issue with the fortran files and you get this error:

building 'ifscube.elprofile' extension
error: unknown file type '.f90' (from 'ifscube/profiles.f90')

[danielrd6]

Indeed, the distutils deprecation requires a significant change in the packaging and installation procedure. I will work on this issue during the coming weeks, but until a solution is implemented we will have to keep using IFSCube in a 3.11 environment.