tt replicaset promote for cartridge

[TarantoolBot]

Product: tt CLI
Since: 2.2+ (not released yet)
Root document:

• a new page in https://www.tarantool.io/en/doc/latest/reference/tooling/tt_cli/commands/
• https://www.tarantool.io/en/doc/latest/reference/tooling/tt_cli/cluster/

SME: @ askalt @ psergee

Details

To do together with other tt replicaset documentation tasks, see #3850.

This patch adds an ability to promote an instance
in the cartridge replicaset with tt replicaset promote.

tt replicaset promote [flags] (<APP_NAME:INSTANCE_NAME> | <URI>)

It operates according to the [1]:

• In the case of "disabled" / "eventual" failover changes the failover priority.
  Please note, in this case, consistency is not guaranteed and replication conflicts may occur.

• In the case of "stateful" / "raft" it calls 'cartridge.failover_promote()' and waits
  with a timeout (can be specified) until the instance transitions to the rw state.
  If -f is specified, it passes "force_inconsistency" as true.

1. https://www.tarantool.io/en/doc/2.11/book/cartridge/cartridge_dev/#manual-leader-promotion

Part of #315
Requested by @askalt in tarantool/tt@e787612.