New ElasticSearch storage option explanation in 9.2.0

Since v9.2.0, SkyWalking OAP provide 2 storage options for metrics/meter and records, system environment variable is (SW_STORAGE_ES_LOGIC_SHARDING):

No-Sharding Model (OAP default setting, SW_STORAGE_ES_LOGIC_SHARDING = false)

1. OAP merge all metrics/meter and records(without super datasets, such as segments) indices into one physical index template metrics-all and records-all.
2. The logic index name would present in column metric_table and record_table.
3. If logic column name has alias (configured by @ElasticSearch.Column()), the alias would be the real physical column name.

No-Sharding Model (SW_STORAGE_ES_LOGIC_SHARDING = true )

1. OAP shard metrics/meter indices into multi-physical indices as the previous versions(one index template per metric/meter aggregation function).
2. Records and metrics without configure aggregation function in @MetricsFunction and @MeterFunction would not be sharded.
3. The shard template name would be metrics-aggregation function name or meter-aggregation function name such as metrics-count, and the logic index name would present in column metric_table.
4. The OAP would not use the column alias, the logic column name would be the real physical column name.

Notice: Users still could choose to adjust ElasticSearch's shard number(SW_STORAGE_ES_INDEX_SHARDS_NUMBER) to scale out no matter the option is.