Add PMD to core to provide some feedback on potential code quality concerns

core/pom.xml

@@ -46,4 +46,14 @@
       <artifactId>commons-codec</artifactId>
     </dependency>
   </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-pmd-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+
 </project>

pom.xml

@@ -903,6 +903,23 @@
             </execution>
           </executions>
         </plugin>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-pmd-plugin</artifactId>
+          <version>3.1</version>
+          <configuration>
+            <failOnViolation>false</failOnViolation>
+          </configuration>
+          <executions>
+            <execution>
+              <id>cloudstack-pmd</id>
+              <goals>
+                <goal>check</goal>
+                <goal>cpd-check</goal>
+              </goals>
+            </execution>
+          </executions>
+        </plugin>
       </plugins>
     </pluginManagement>
   </build>