[BUILD] Release version should match latest version

This commit ensures that the latest version in our code is identical
to the project.version specified in the pom.xml file.

pom.xml

@@ -515,6 +515,7 @@
                                 <tests.cluster>${tests.cluster}</tests.cluster>
                                 <tests.heap.size>${tests.heap.size}</tests.heap.size>
                                 <tests.filter>${tests.filter}</tests.filter>
+                                <tests.version>${project.version}</tests.version>
                                 <es.node.local>${env.ES_TEST_LOCAL}</es.node.local>
                                 <es.node.mode>${es.node.mode}</es.node.mode>
                                 <es.logger.level>${es.logger.level}</es.logger.level>

src/test/java/org/elasticsearch/VersionTests.java

@@ -36,6 +36,16 @@ import static org.hamcrest.Matchers.sameInstance;
 
 public class VersionTests extends ElasticsearchTestCase {
 
+    @Test
+    public void testMavenVersion() {
+        // maven sets this property to ensure that the latest version
+        // we use here is the version that is actually set to the project.version
+        // in maven
+        String property = System.getProperty("tests.version", null);
+        assumeNotNull(property);
+        assertEquals(property, Version.CURRENT.toString());
+    }
+
     @Test
     public void testVersions() throws Exception {
         assertThat(V_0_20_0.before(V_0_90_0), is(true));