* Add desc for system tables.

* Fixed links, add comments from the developer

* Update docs/en/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/settings_profile_elements.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/settings_profile_elements.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/settings_profile_elements.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/en/operations/system-tables/users.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Link to Enum.

* Added translation to russian

* Update row_policies.md

* Add lost description

* Update docs/ru/operations/system-tables/grants.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/ru/operations/system-tables/grants.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/ru/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Update docs/ru/operations/system-tables/row_policies.md
Co-authored-by: NBayoNet <da-daos@yandex.ru>

* Additions

* Fixed links
Co-authored-by: NAnna Devyatova <annadevyatova@yandex-team.ru>
Co-authored-by: NBayoNet <da-daos@yandex.ru>