Couchbase

Couchbase server option	Environment variable	PDS default value
`--services`	`COUCHBASE_SERVICES`	`data, index, query, fts`
`--cluster-ramsize`	`COUCHBASE_RAMSIZE`	`2048`
`--cluster-index-ramsize`	`COUCHBASE_INDEX_RAMSIZE`	`512`
`--cluster-fts-ramsize`	`COUCHBASE_FTS_RAMSIZE`	`512`
`--index-storage-setting`	`COUCHBASE_INDEX_STORAGE_SETTING`	`default`
`--enable-auto-failover`	`COUCHBASE_ENABLE_AUTO_FAILOVER`	`1`
`--auto-failover-timeout`	`COUCHBASE_AUTO_FAILOVER_TIMEOUT`	`180`