Support overriding thresholds through config

[Alex-Burmak]

No description provided.

[Alex-Burmak]

Relates to https://st.yandex-team.ru/MDB-28487

[Alex-Burmak]

Moved to config file.

Default values are still present in help messages:

# chadmin wait replication-sync -h
Usage: chadmin wait replication-sync [OPTIONS]

  Wait for ClickHouse server to sync replication with other replicas.

Options:
  --replica-timeout TIMESPAN      Timeout for SYNC REPLICA command.  [default: 1h]
  --total-timeout TIMESPAN        Max amount of time to wait.  [default: 3d]
  -s, --status INTEGER            Wait until replication-lag returned status is no worse than given, 0 = OK, 1 = WARN, 2
                                  = CRIT.  [default: 0]
  -p, --pause TIMESPAN            Pause between replication lag requests.  [default: 30s]
  -x, --exec-critical INTEGER     Critical threshold for one task execution.  [default: 3600]
  -c, --critical INTEGER          Critical threshold for lag with errors.  [default: 600]
  -w, --warning INTEGER           Warning threshold.  [default: 300]
  -M, --merges-critical FLOAT RANGE
                                  Critical threshold in percent of max_replicated_merges_in_queue.  [default: 90.0;
                                  0.0<=x<=100.0]
  -m, --merges-warning FLOAT RANGE
                                  Warning threshold in percent of max_replicated_merges_in_queue.  [default: 50.0;
                                  0.0<=x<=100.0]
  -h, --help                      Show this message and exit.  [default: False]