*: Enable refactored authority discovery (#624)

* *: Enable authority discovery module

* *: List authority discovery id after parachain validator id

Make sure existing key types don't change their order by appending the
authority discovery id instead of injecting it between im online id and
parachain validator id.

* *: Gate authority discovery module behind feature flag

* cli/src/lib.rs: Fix warnings

* cli/src/lib.rs: Shorten line length