feat: --config parameter to specify picodata configuration file

Summary

• Remove --init-cfg option: now it will say to use --config instead

• fix: move tiers configuration to config.yaml

Change configuration file format:

• before:

tier:
  storage:
    replication_factor: 2

• after:

cluster:
  tiers:
    storage:
      replication-factor: 2

• feat: try reading ./config.yaml by default

• feat: validate configuration against storage (currently only instance_id)

• feat: --config parameter to specify picodata configuration file

Also here we refactor all the places where we checked command line parameters, because now PicodataConfig is the main source of this information.

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• Close #...
• Target branch: master
• Changes should be cherry-picked to 24.1: yes / no
• Docs follow-up: not necessary / new issue