Adding Elasticsearch to Supported Technologies page (#286)

Author: eyalkoren

docs/supported-technologies.asciidoc

@@ -114,6 +114,11 @@ Other Servlet 3+ compliant servers will most likely work as well.
 |The agent automatically creates DB spans for all your JDBC queries.
  This includes JDBC queries executed by O/R mappers like Hibernate.
 
+|Elasticsearch
+|5.0.2+
+|The agent automatically creates Elasticsearch spans for queries done through the official REST client.
+ *Currently, the `*Async` methods are not supported, only their synchronous counterparts.*
+
 |===
 
 [float]