Fix maven compile configuration for jdk 1.7

pom.xml

@@ -23,16 +23,22 @@
 		<pluginManagement>
 			<plugins>
 				<plugin>
-					<artifactId>maven-compiler-plugin</artifactId>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-compiler-plugin</artifactId>
 					<version>2.5</version>
-					<configuration>
-						<source>1.7</source>
-						<target>1.7</target>
-					</configuration>
 				</plugin>
 			</plugins>
 		</pluginManagement>
-	</build>
+        <plugins>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.7</source>
+                    <target>1.7</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
 
 	<dependencies>
 		<dependency>