Добавить activation_deadline в конфиг файл

Summary

This patch allows to configure parameter activation_deadline for each instance in the configuration yaml. By default, the value set to 2 * 60 * 60 = 7200 sec (2 hours) which defines the maximum time that instance will wait to be activated and join a cluster. If the activation doesn't occur within this period the instance will shut down.

• Close #1175 (closed)
• Cherry-pick to: none
• Docs follow-up: docs#489 (closed)
• Changelog is updated

Closes #1175 (closed)