Update translog.asciidoc

Documented `index.gateway.local.sync`
[BUILD] Add profile that skips all validations

This commit adds a profile that skips all validation ie.
 - nocommit / tabs checking
 - forbidden API checks
 - license headers

It's not active by default but can easily be activated with
  `mvn -Pdev` or in the `~/.m2/settings.xml`

for reference see:
  http://maven.apache.org/guides/introduction/introduction-to-profiles.html
[TEST] Increased logging and make use of prepareCreate and assertAcked
[TEST] All shards should be allocated before snapshotting & restoring
cluster block with auto create index bulk action can cause bulk execution to not return
when there is a cluster block (like no master yet discovered), the bulk action doesn't properly catch the exception of inner execute to notify the listener, causing the bulk operation to hang
closes #7086
_geo_distance sort: allow many to many geo point distance

Add computation of disyance to many geo points. Example request:

```
{
  "sort": [
    {
      "_geo_distance": {
        "location": [
          {
            "lat":1.2,
            "lon":3
          },
          {
             "lat":1.2,
            "lon":3
          }
        ],
        "order": "desc",
        "unit": "km",
        "sort_mode": "max"
      }
    }
  ]
}
```

closes #3926
[TEST] Reduce number of updates and wait after 1st NoNodeException.