Bring up to date with v3

[elisachisari]

CCL is now almost at v3. We should make sure the notebooks follow the new API. These ones need checking:

• [x] Angular cross-correlations.ipynb
• [x] Halo-model-Pk.ipynb
• [x] Baryons_halo_model_power_spectrum.ipynb
• [x] MCMC Likelihood Analysis.ipynb
• [x] CalculatorMode.ipynb
• [x] MG_mu_Sigma_with_z_and_k_dependences.ipynb
• [x] CellsCorrelations.ipynb
• [x] MG_mu_Sigma_with_z_dependence_only.ipynb
• [x] Distance Calculations Example.ipynb
• [x] MG_mu_sigma_examples.ipynb
• [x] GeneralizedTracers.ipynb
• [x] PerturbationTheoryPk.ipynb
• [x] Halo profiles.ipynb
• [x] Power spectrum example.ipynb
• [x] Halo-mass-function-example.ipynb
• [x] Reading-writing-Cosmology-objects.ipynb

Do any new functionalities need to be identified?

[nikosarcevic]

sounds like a plan! I know a few typos here and there and will be looking into this.

regarding the functionalities in ccl per se, I personally think that we might want to reconsider how hmcode is called now. I am not sure if this is being discussed with the wonderful folk who work on cclv3 but I think how we have it now is not so user friendly.

for other functionalities in the notebooks, I will have to think about it