This PR renames the CRUD APIS for ILM GET _ilm/<policy>, _ilm -> _ilm/policy/<policy>, _ilm/policy PUT _ilm/<policy> -> _ilm/policy/<policy> DELETE _ilm/<policy> -> _ilm/policy/<policy> closes #34929.
closes #34927.
we are restructuring the docs, this migrates ILM docs outside of the x-pack doc structure.