[25] Add Chebyshev basis

[MothNik]

This pull request

🦾 Enhancements

• implements the Chebyshev polynomials of first and second kind as an alternative to the Hermite functions (both a class and a function interface)

✅❌ Tests

• adds test for the Chebyshev polynomials that are analogous to those of the Hermite functions

✍️ Documentation

• adds an initial sketch of an example and a README section for the Chebyshev polynomials

Prepares #25

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Files	Coverage Δ
src/robust_fourier/__init__.py	100.00% <100.00%> (ø)
src/robust_fourier/_utils/__init__.py	100.00% <100.00%> (ø)
src/robust_fourier/_utils/_numba_helpers.py	100.00% <ø> (ø)
src/robust_fourier/_utils/_validate.py	100.00% <100.00%> (ø)
src/robust_fourier/_utils/_x_preprocessing.py	100.00% <100.00%> (ø)
...c/robust_fourier/chebyshev_polynomials/__init__.py	100.00% <100.00%> (ø)
..._fourier/chebyshev_polynomials/_class_interface.py	100.00% <100.00%> (ø)
...t_fourier/chebyshev_polynomials/_func_interface.py	100.00% <100.00%> (ø)
...bust_fourier/chebyshev_polynomials/_numba_funcs.py	100.00% <100.00%> (ø)
...bust_fourier/chebyshev_polynomials/_numpy_funcs.py	100.00% <100.00%> (ø)
... and 4 more