Add more features to elasticsearch

[yii-bot]

trafficstars

This issue has originally been reported by @cebe at https://github.com/yiisoft/yii2/issues/1313. Moved here by @cebe.

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To make elasticsearch support complete.

Moved these from #1295 as we can easily add them later and they are nice to have.

• [x] make use of native optimistic locking support
• [x] implement versioning
• [ ] api to retrieve parents and children (see also https://github.com/yiisoft/yii2/issues/5758#issuecomment-65063787)
• [x] make index and type available in instantiate (#2289)
• [x] implement updateAllCounters(), see for details elasticsearch/elasticsearch#1583
• [ ] implement copy() and move() as PK change is not supported

[githubjeka]

Good job bot. :)

[beowulfenator]

This will be more useful in 2.1