Lightweight docs revamp for v2.last

[damonge]

The docs can be viewed here: https://ccl.readthedocs.io/en/docs_v2last_lite/

[coveralls]

Pull Request Test Coverage Report for Build 5005392826

• 90 of 90 (100.0%) changed or added relevant lines in 42 files are covered.
• 6 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.003%) to 97.136%

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Files with Coverage Reduction	New Missed Lines	%
pyccl/tk3d.py	1	96.97%
pyccl/pk2d.py	2	96.42%
pyccl/halos/halo_model_base.py	3	94.34%

Totals
Change from base Build 4928207173:	0.003%
Covered Lines:	6003
Relevant Lines:	6180

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💛 - Coveralls

[nikfilippas]

Don't do that, it will be super confusing for people to refer to it with 2 different names.
What you need to do is remove spline_params from the imports at the top, and replace the lines in the function with:

if spline_params is None:
    from . import spline_params

Much neater, and you get to keep the same name. We use params to refer to parameters everywhere in CCL. Let's be consistent. (See the docs_v3 PR)

[damonge]

Yep, done.

[carlosggarcia]

I got finally through it. I have added quite a few of comments/questions. None important. Most of them typos or things that I don't see clearly

[carlosggarcia]

Minor change requested.

[damonge]

Thanks again @carlosggarcia . Back to you!

[carlosggarcia]

LGTM!