feat: update directive to be standalone

[shanmukhateja]

Changes

• Set directive as standalone

• Remove DatatablesModule from repo

• Update documentation & unit tests

• Add background to single-line code blocks which uses <code> HTML tag

Plans

I couldn't find documentation to create "migrations" found during ng update to make this a new minor release.

Hence, this change should be released in next major release to not break v14 apps which currently use DatatablesModule.

[l-lin]

It seems to be a feature preview:

The standalone component feature is available for developer preview. It's ready for you to try; but it might change before it is stable.

Mmh I'm not sure it's safe to have this enhancement before having a stable feature.