docs(elasticsearch): updated elasticsearch with info about templating and pipeline metrics

docs/sources/datasources/elasticsearch.md

@@ -53,6 +53,35 @@ a time pattern for the index name or a wildcard.
 The Elasticsearch query editor allows you to select multiple metrics and group by multiple terms or filters. Use the plus and minus icons to the right to add / remove
 The Elasticsearch query editor allows you to select multiple metrics and group by multiple terms or filters. Use the plus and minus icons to the right to add / remove
 metrics or group bys. Some metrics and group by have options, click the option text to expand the the row to view and edit metric or group by options.
 metrics or group bys. Some metrics and group by have options, click the option text to expand the the row to view and edit metric or group by options.
 
 
+## Pipeline metrics
+
+If you have Elasticsearch 2.x and Grafana 2.6 or above then you can use pipeline metric aggregations like
+**Moving Average** and **Derivative**. Elasticsearch pipeline metrics require another metric to be based on. Use the eye icon next to the metric
+to hide metrics from appearing in the graph. This is useful for metrics you only have in the query to be used
+in a pipeline metric.
+
+![](/img/elasticsearch/pipeline_metrics_editor.png)
+
+## Templating
+
+The Elasticsearch datasource supports two types of queries you can use to fill template variables with values.
+
+### Possible values for a field
+
+```json
+{"find": "terms", "field": "@hostname"}
+```
+
+### Fields filtered by type
+```json
+{"find": "fields", "type": "string"}
+```
+
+### Multi format / All format
+Use lucene format.
+
+
+
 ## Annotations
 ## Annotations
 TODO
 TODO