tt CLI (2.10): `tt tcm stop` command

[TarantoolBot]

Product: tt CLI
Since: tt 2.10.0
Audience/target: all
Dev ticket: https://jira.vk.team/browse/TNTP-1993
Root document:

• [New page] https://www.tarantool.io/en/doc/latest/reference/tooling/tt_cli/tcm/
• https://www.tarantool.io/en/doc/latest/tooling/tcm/ ?

SME: @ AlexandrLitkevich

Details

Add command tt tcm stop to gracefully terminate TCM:

• Works in both modes(watchdog and interactive)
• Stops all subprocesses

Closes #TNTP-1993
Requested by @AlexandrLitkevich in tarantool/tt@8c81e5e.