Add documentation for adaptive metrics and CRF score

[candicemyt]

Description

Add the missing theoretical documentation on the conformity scores.
Add examples of how to use and interpret the new metrics.
Add a tutorial on the CRF score.

Fixes #331

Type of change

• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Checklist

• I have read the contributing guidelines
• I have updated the HISTORY.rst and AUTHORS.rst files
• Linting passes successfully : make lint
• Typing passes successfully : make type-check
• Unit tests pass successfully : make tests
• Coverage is 100% : make coverage
• Documentation builds successfully : make doc

[codecov-commenter]

Codecov Report

Patch has no changes to coverable lines.

❗ Current head 5701d75 differs from pull request most recent head 37492b6. Consider uploading reports for the commit 37492b6 to get more accurate results

Files Changed	Coverage
...ie/conformity_scores/residual_conformity_scores.py	ø
mapie/metrics.py	ø

📢 Thoughts on this report? Let us know!.

[thibaultcordier]

@candicemyt, the problem of compiling documentation is now solved. I suggest you merge your branch with the master branch as follows (in your local branch):

git merge master

Consult https://git-scm.com/docs/git-merge if you have any difficulties, or ask me.

[thibaultcordier]

It looks fine to me. The previous comments have been taken into account.

[LacombeLouis]

Great PR! It's much better to understand how CRF works. I would add a couple more comments to explain the results 😃