DATAES-289 - Upgraded to Elasticsearch 2.4.

Upgraded to Elasticsearch 2.4 as version before that are not compatiblewith Jackson 2.8 [0].

Removed the now unsupported Groovy plugin registration way and added groovy-lang as test scope dependency but had to disable the only Groovy related test as it seems to be unclear how to activate the Groovy plugin in an embedded Elasticsearch server [1].

[0] https://github.com/elastic/elasticsearch/issues/20089
[1] https://discuss.elastic.co/t/after-upgrade-from-es-2-1-1-to-es-2-2-0-groovy-scripting-is-broken/40977

pom.xml

@@ -23,8 +23,7 @@
 
         <commonscollections>3.2.1</commonscollections>
         <commonslang>2.6</commonslang>
-        <elasticsearch>2.3.3</elasticsearch>
-        <jackson>2.7.5</jackson>
+        <elasticsearch>2.4.0</elasticsearch>
         <springdata.commons>1.13.0.BUILD-SNAPSHOT</springdata.commons>
 
     </properties>
@@ -88,6 +87,14 @@
             <version>${jackson}</version>
         </dependency>
 
+        <!-- Groovy -->
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy-all</artifactId>
+            <version>2.4.4</version>
+            <scope>test</scope>
+        </dependency>
+
         <!-- CDI -->
         <dependency>
             <groupId>javax.enterprise</groupId>