update metadata

add python 3.10/3.11

Merge pull request #77 from cokelaer/add_python39

Fixing deprecated function of Scipy.

increase version and update doc

update metadata (new version) and changelog

Create CONTRIBUTING.rst

[ci skip]

Merge branch 'master' of https://github.com/cokelaer/spectrum

version 0.6.1 posted on pypi