Missing `znodes` docstrings + broken links in docs

[briochemc]

Links to znodes, e.g., in https://clima.github.io/OceananigansDocumentation/stable/appendix/library/#Oceananigans.Grids.ynodes-NTuple{4,%20Any}, are broken (404).

I guess it's because there is no znodes docstring?

julia> using Oceananigans

help?> znodes
search: znodes nodes rnodes ynodes φnodes λnodes xnodes ones names undef

  No documentation found for public binding Oceananigans.Grids.znodes.

  Oceananigans.Grids.znodes is a Function.

[glwagner]

These two versions need docstrings:

Oceananigans.jl/src/Grids/vertical_discretization.jl

Lines 212 to 213 in d6978bb

	@inline znodes(grid::AUG, ℓz; kwargs...) = rnodes(grid, ℓz; kwargs...)
	@inline znodes(grid::AUG, ℓx, ℓy, ℓz; kwargs...) = rnodes(grid, ℓx, ℓy, ℓz; kwargs...)

[briochemc]

All the other docstrings (xnodes, ynodes, etc.) point to znodes examples:

See znodes for examples.

But did these znodes examples ever exist? (Wondering if I should add such examples, or remove those links altogether)

[glwagner]

I am sure they did exist and they would be things like, build a grid with 3 grid points, and show the output of znodes. @navidcy might be willing to dig those up from git history. pretty confused where they went

[glwagner]

thanks for uncovering this!

[giordano]

Oceananigans.jl/docs/make.jl

Line 216 in ac5e226

warnonly = [:cross_references],

😞

[giordano]

There are lots of warnings: https://buildkite.com/clima/oceananigans/builds/27478#019b0eb9-8eee-4bc8-a5ed-e590e834ad75/38-3396

┌ Warning: Cannot resolve @ref for md"[`Ω_Earth`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Coriolis.Ω_Earth`.
│ - No docstring found in doc for binding `Main.Ω_Earth`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl
[...]
┌ Warning: Cannot resolve @ref for md"[`TransposableField`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.DistributedComputations.TransposableField`.
│ - No docstring found in doc for binding `Main.TransposableField`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`znodes`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`znodes`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`znodes`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`znodes`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`znodes`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
│ - No docstring found in doc for binding `Oceananigans.Grids.znodes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`materialize_free_surface`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Models.materialize_free_surface`.
│ - No docstring found in doc for binding `Main.materialize_free_surface`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`UpwindBiased`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Advection.UpwindBiased`.
│ - No docstring found in doc for binding `Oceananigans.Advection.UpwindBiased`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`ConformalCubedSphereGrid`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Operators.ConformalCubedSphereGrid`.
│ - Fallback resolution in Main for `ConformalCubedSphereGrid` -> `Oceananigans.MultiRegion.ConformalCubedSphereGrid` is only allowed for fully qualified names
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`ConformalCubedSphereGrid`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.Operators.ConformalCubedSphereGrid`.
│ - Fallback resolution in Main for `ConformalCubedSphereGrid` -> `Oceananigans.MultiRegion.ConformalCubedSphereGrid` is only allowed for fully qualified names
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`required_checkpoint_properties`](@ref)" in docs/src/appendix/library.md.
│ - No docstring found in doc for binding `Oceananigans.OutputWriters.required_checkpoint_properties`.
│ - No docstring found in doc for binding `Main.required_checkpoint_properties`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[schedules](@ref schedules)" in docs/src/simulations/simulations_overview.md.
│ - No docstring found in doc for binding `Main.schedules`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`yspacings`](@ref)" in docs/src/grids.md.
│ - No docstring found in doc for binding `Oceananigans.Grids.yspacings`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
[...]
┌ Warning: Cannot resolve @ref for md"[`set!`](@ref)" in docs/src/fields.md.
│ - No docstring found in doc for binding `Oceananigans.Fields.set!`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`SmagorinskyLilly`](@ref)" in docs/src/models/turbulence_closures.md.
│ - No docstring found in doc for binding `Oceananigans.TurbulenceClosures.Smagorinskys.SmagorinskyLilly`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`Oceananigans.Utils.AbstractSchedule`](@ref Oceananigans.Utils.AbstractSchedule)" in docs/src/simulations/schedules.md.
│ - No docstring found in doc for binding `Oceananigans.Utils.AbstractSchedule`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49
┌ Warning: Cannot resolve @ref for md"[`AveragedSpecifiedTimes`](@ref Oceananigans.OutputWriters.AveragedSpecifiedTimes)" in docs/src/simulations/schedules.md.
│ - No docstring found in doc for binding `Oceananigans.OutputWriters.AveragedSpecifiedTimes`.
└ @ Documenter ~/.julia-oceananigans/packages/Documenter/xvqbW/src/utilities/utilities.jl:49