Update to pmd plugin 3.4 and plugin-plugin 3.4 and jetty-build-support 1.4

jetty-maven-plugin/pom.xml

@@ -8,9 +8,10 @@
   <artifactId>jetty-maven-plugin</artifactId>
   <packaging>maven-plugin</packaging>
   <name>Jetty :: Jetty Maven Plugin</name>
+  <description>Jetty maven plugins</description>
   <properties>
     <mavenVersion>3.0.3</mavenVersion>
-    <pluginToolsVersion>3.1</pluginToolsVersion>
+    <pluginToolsVersion>3.4</pluginToolsVersion>
     <bundle-symbolic-name>${project.groupId}.maven.plugin</bundle-symbolic-name>
   </properties>
   <build>
@@ -73,7 +74,6 @@
             <id>exec-plugin-doc</id>
             <phase>generate-sources</phase>
             <goals>
-              <goal>xdoc</goal>
               <goal>helpmojo</goal>
             </goals>
           </execution>

pom.xml

@@ -13,7 +13,7 @@
   <properties>
     <jetty.url>http://www.eclipse.org/jetty</jetty.url>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <build-support-version>1.1</build-support-version>
+    <build-support-version>1.4</build-support-version>
     <slf4j-version>1.6.6</slf4j-version>
     <jetty-test-policy-version>1.2</jetty-test-policy-version>
     <alpn.api.version>1.1.2.v20150522</alpn.api.version>
@@ -189,7 +189,7 @@
           </execution>
         </executions>
         <configuration>
-          <targetJdk>1.7</targetJdk>
+          <targetJdk>1.8</targetJdk>
           <rulesets>
             <ruleset>jetty/pmd_logging_ruleset.xml</ruleset>
           </rulesets>
@@ -403,7 +403,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-pmd-plugin</artifactId>
-          <version>2.7.1</version>
+          <version>3.4</version>
         </plugin>
       </plugins>
     </pluginManagement>