Add customizations for th, tr, and td tags in Table module

[skaerg]

This PR aims to

• use the rowAttrs customization since it was present in the code but actually unused until now.
• rename rowAttrs to trAttrs
• change the type of the customizations so that all instances of Attribute (Msg msg) are replaced with Attribute msg so that it is easier for the parent component to create attributes that depend on parent msgs
• add the option to add column-specific html attributes on entries (tdAttrs) and on columns themselves (thAttrs)

[clarktsiory]

Nice ! Since it's always a list, and repeats across functions, it could even be factored out

Could you also update the title, so that we have Table in it ? (the library contains something else than table, it makes it easier to trace)

[clarktsiory]

this could be extracted outside of the view

[clarktsiory]

this could even be

mapAttributes =
    List.map Html.Attributes.map ParentMsg

[clarktsiory]

this could be

Suggested change

	tr (List.map (Html.Attributes.map ParentMsg) (rowAttrs n))
	tr (mapAttributes (rowAttrs n))

[clarktsiory]

Suggested change

	(List.map (Html.Attributes.map ParentMsg) entryAttrs)
	(mapAttributes entryAttrs)

[clarktsiory]

Suggested change

	++ List.map (Html.Attributes.map ParentMsg) columnAttrs
	++ mapAttributes columnAttrs

[clarktsiory]

all could be |> mapAttributes since they are are lists

[clarktsiory]

So, this changes the API of Column significantly : we will need to provide explicit "customizations" on the column every time we instantiate it.
If we are ready to have them within Column, we may need to provide a "column builder" for convenience, as it would more often be empty...

But this primarily raises some inconsistency in the API, these clearly belong to Customizations.
Moreover, the naming of customizations are based on the HTML element that is being customized, respectively th and td here.

And it's true that they are "cell"/"header"-specific, so, is it not possible to have :

type alias Customizations row msg =
   ...
   , thAttrs : Column row msg -> List (Attribute msg)
   , tdAttrs : Column row msg -> List (Attribute msg)

?

[clarktsiory]

Great !
Edit : but see the comment below

[clarktsiory]

So, the title of the PR is being divergent with the change that is made, and it indicates there is something still wrong : rowAttrs should be trAttrs 😅

And the real thing this PR is doing is : adding customizations for tr, td, th