Documentation on SunZenithCorrector and EffectiveSolarPathlengthCorrector modifiers contradicts itself

[gerritholl]

Describe the bug

In the documentation for the SunZenithCorrector modifier, the class docstring says that beyond the correction_limit, correction is gradually reduced unless max_sza is None, in which case it's constant:

satpy/satpy/modifiers/geometry.py

Lines 80 to 85 in 40a62fa

	In addition to adjusting the provided reflectances by the cosine of the
	solar zenith angle, this modifier forces all reflectances beyond a
	solar zenith angle of ``max_sza`` to 0. It also gradually reduces the
	amount of correction done between ``correction_limit`` and ``max_sza``. If
	``max_sza`` is ``None`` then a constant correction is applied to zenith
	angles beyond ``correction_limit``.

In the function initialisation docstring, it says the correction beyond correction_limit is constant:

satpy/satpy/modifiers/geometry.py

Lines 103 to 105 in 40a62fa

	correction_limit (float): Maximum solar zenith angle to apply the
	correction in degrees. Pixels beyond this limit have a
	constant correction applied. Default 88.

I think the class docstring is correct and the initialisation docstring is wrong (unless max_sza=None).

The same discrepancy exists for the EffectiveSolarPathlengthCorrector.

Class docstring:

satpy/satpy/modifiers/geometry.py

Lines 128 to 131 in 40a62fa

	It also gradually reduces the amount of correction done between
	``correction_limit`` and ``max_sza``. If ``max_sza`` is ``None`` then a
	constant correction is applied to zenith angles beyond
	``correction_limit``.

Init docstring:

satpy/satpy/modifiers/geometry.py

Lines 149 to 151 in 40a62fa

	correction_limit (float): Maximum solar zenith angle to apply the
	correction in degrees. Pixels beyond this limit have a
	constant correction applied. Default 88.

[djhoese]

Maybe the best fix for this is to add to the correction_limit description:

...have a constant correction applied is ``max_sza`` is ``None``, otherwise the correction is gradually reduced to 0 at ``max_sza``.

Or even just See class docstring for more information. since this information is essentially being repeated.